Actually load index cache again (fixes #45)

CONTRIBUTING.md

@@ -0,0 +1,22 @@
+Please do contribute!
+
+## Building
+
+[See the wiki](https://github.com/calmh/syncthing/wiki/Building)
+
+## Tests
+
+Yes please!
+
+## Style
+
+`go fmt`
+
+## Documentation
+
+[Hack it here](https://github.com/calmh/syncthing/wiki)
+
+## License
+
+MIT
+

build.sh

@@ -3,22 +3,18 @@
 version=$(git describe --always)
 buildDir=dist
 
-if [[ $1 == "-f" ]] ; then
-	fast=yes
-	shift
-fi
-
 if [[ $fast != yes ]] ; then
 	go get -d
 	go test ./...
 fi
 
 if [[ -z $1 ]] ; then
-	go build -ldflags "-X main.Version $version" \
-	&& nrsc syncthing gui
+	go build -ldflags "-X main.Version $version"
+elif [[ $1 == "embed" ]] ; then
+	embedder auto gui > auto/gui.files.go \
+	&& go build -ldflags "-X main.Version $version"
 elif [[ $1 == "tar" ]] ; then
 	go build -ldflags "-X main.Version $version" \
-	&& nrsc syncthing gui \
 	&& mkdir syncthing-dist \
 	&& cp syncthing README.md LICENSE syncthing-dist \
 	&& tar zcvf syncthing-dist.tar.gz syncthing-dist \
@@ -34,7 +30,6 @@ elif [[ $1 == "all" ]] ; then
 			export GOARCH="$goarch"
 			export name="syncthing-$goos-$goarch"
 			go build -ldflags "-X main.Version $version" \
-				&& nrsc syncthing gui \
 				&& mkdir -p "$name" \
 				&& cp syncthing "$buildDir/$name" \
 				&& cp README.md LICENSE "$name" \
@@ -53,7 +48,6 @@ elif [[ $1 == "all" ]] ; then
 				export GOARCH="$goarch"
 				export name="syncthing-$goos-${goarch}v$goarm"
 				go build -ldflags "-X main.Version $version" \
-					&& nrsc syncthing gui \
 					&& mkdir -p "$name" \
 					&& cp syncthing "$buildDir/$name" \
 					&& cp README.md LICENSE "$name" \
@@ -71,10 +65,10 @@ elif [[ $1 == "all" ]] ; then
 			export GOARCH="$goarch"
 			export name="syncthing-$goos-$goarch"
 			go build -ldflags "-X main.Version $version" \
-				&& nrsc syncthing.exe gui \
 				&& mkdir -p "$name" \
-				&& mv syncthing.exe "$buildDir/$name.exe" \
+				&& cp syncthing.exe "$buildDir/$name.exe" \
 				&& cp README.md LICENSE "$name" \
+				&& mv syncthing.exe "$name" \
 				&& zip -qr "$buildDir/$name.zip" "$name" \
 				&& rm -r  "$name"
 		done

config.go

@@ -0,0 +1,129 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"reflect"
+	"strconv"
+	"strings"
+	"text/template"
+	"time"
+)
+
+type Options struct {
+	Listen            string        `ini:"listen-address" default:":22000" description:"ip:port to for incoming sync connections"`
+	ReadOnly          bool          `ini:"read-only" description:"Allow changes to the local repository"`
+	Delete            bool          `ini:"allow-delete" default:"true" description:"Allow deletes of files in the local repository"`
+	Symlinks          bool          `ini:"follow-symlinks" default:"true" description:"Follow symbolic links at the top level of the repository"`
+	GUI               bool          `ini:"gui-enabled" default:"true" description:"Enable the HTTP GUI"`
+	GUIAddr           string        `ini:"gui-address" default:"127.0.0.1:8080" description:"ip:port for GUI connections"`
+	ExternalServer    string        `ini:"global-announce-server" default:"syncthing.nym.se:22025" description:"Global server for announcements"`
+	ExternalDiscovery bool          `ini:"global-announce-enabled" default:"true" description:"Announce to the global announce server"`
+	LocalDiscovery    bool          `ini:"local-announce-enabled" default:"true" description:"Announce to the local network"`
+	ParallelRequests  int           `ini:"parallel-requests" default:"16" description:"Maximum number of blocks to request in parallel"`
+	LimitRate         int           `ini:"max-send-kbps" description:"Limit outgoing data rate (kbyte/s)"`
+	ScanInterval      time.Duration `ini:"rescan-interval" default:"60s" description:"Scan repository for changes this often"`
+	ConnInterval      time.Duration `ini:"reconnection-interval" default:"60s" description:"Attempt to (re)connect to peers this often"`
+	MaxChangeBW       int           `ini:"max-change-bw" default:"1000" description:"Suppress files changing more than this (kbyte/s)"`
+}
+
+func loadConfig(m map[string]string, data interface{}) error {
+	s := reflect.ValueOf(data).Elem()
+	t := s.Type()
+
+	for i := 0; i < s.NumField(); i++ {
+		f := s.Field(i)
+		tag := t.Field(i).Tag
+
+		name := tag.Get("ini")
+		if len(name) == 0 {
+			name = strings.ToLower(t.Field(i).Name)
+		}
+
+		v, ok := m[name]
+		if !ok {
+			v = tag.Get("default")
+		}
+		if len(v) > 0 {
+			switch f.Interface().(type) {
+			case time.Duration:
+				d, err := time.ParseDuration(v)
+				if err != nil {
+					return err
+				}
+				f.SetInt(int64(d))
+
+			case string:
+				f.SetString(v)
+
+			case int:
+				i, err := strconv.ParseInt(v, 10, 64)
+				if err != nil {
+					return err
+				}
+				f.SetInt(i)
+
+			case bool:
+				f.SetBool(v == "true")
+
+			default:
+				panic(f.Type())
+			}
+		}
+	}
+	return nil
+}
+
+type cfg struct {
+	Key     string
+	Value   string
+	Comment string
+}
+
+func structToValues(data interface{}) []cfg {
+	s := reflect.ValueOf(data).Elem()
+	t := s.Type()
+
+	var vals []cfg
+	for i := 0; i < s.NumField(); i++ {
+		f := s.Field(i)
+		tag := t.Field(i).Tag
+
+		var c cfg
+		c.Key = tag.Get("ini")
+		if len(c.Key) == 0 {
+			c.Key = strings.ToLower(t.Field(i).Name)
+		}
+		c.Value = fmt.Sprint(f.Interface())
+		c.Comment = tag.Get("description")
+		vals = append(vals, c)
+	}
+	return vals
+}
+
+var configTemplateStr = `[repository]
+{{if .comments}}; The directory to synchronize. Will be created if it does not exist.
+{{end}}dir = {{.dir}}
+
+[nodes]
+{{if .comments}}; Map of node ID to addresses, or "dynamic" for automatic discovery. Examples:
+; J3MZ4G5O4CLHJKB25WX47K5NUJUWDOLO2TTNY3TV3NRU4HVQRKEQ = 172.16.32.24:22000
+; ZNJZRXQKYHF56A2VVNESRZ6AY4ZOWGFJCV6FXDZJUTRVR3SNBT6Q = dynamic
+{{end}}{{range $n, $a := .nodes}}{{$n}} = {{$a}}
+{{end}}
+[settings]
+{{range $v := .settings}}; {{$v.Comment}}
+{{$v.Key}} = {{$v.Value}}
+{{end}}
+`
+
+var configTemplate = template.Must(template.New("config").Parse(configTemplateStr))
+
+func writeConfig(wr io.Writer, dir string, nodes map[string]string, opts Options, comments bool) {
+	configTemplate.Execute(wr, map[string]interface{}{
+		"dir":      dir,
+		"nodes":    nodes,
+		"settings": structToValues(&opts),
+		"comments": comments,
+	})
+}

discover/discover.go

@@ -100,7 +100,6 @@ type Discoverer struct {
 	MyID             string
 	ListenPort       int
 	BroadcastIntv    time.Duration
-	ExtListenPort    int
 	ExtBroadcastIntv time.Duration
 
 	conn         *net.UDPConn
@@ -114,7 +113,7 @@ type Discoverer struct {
 // When we hit this many errors in succession, we stop.
 const maxErrors = 30
 
-func NewDiscoverer(id string, port int, extPort int, extServer string) (*Discoverer, error) {
+func NewDiscoverer(id string, port int, extServer string) (*Discoverer, error) {
 	local4 := &net.UDPAddr{IP: net.IP{0, 0, 0, 0}, Port: AnnouncementPort}
 	conn, err := net.ListenUDP("udp4", local4)
 	if err != nil {
@@ -125,7 +124,6 @@ func NewDiscoverer(id string, port int, extPort int, extServer string) (*Discove
 		MyID:             id,
 		ListenPort:       port,
 		BroadcastIntv:    30 * time.Second,
-		ExtListenPort:    extPort,
 		ExtBroadcastIntv: 1800 * time.Second,
 
 		conn:      conn,
@@ -138,7 +136,7 @@ func NewDiscoverer(id string, port int, extPort int, extServer string) (*Discove
 	if disc.ListenPort > 0 {
 		disc.sendAnnouncements()
 	}
-	if len(disc.extServer) > 0 && disc.ExtListenPort > 0 {
+	if len(disc.extServer) > 0 {
 		disc.sendExtAnnouncements()
 	}
 
@@ -153,13 +151,13 @@ func (d *Discoverer) sendAnnouncements() {
 }
 
 func (d *Discoverer) sendExtAnnouncements() {
-	extIP, err := net.ResolveUDPAddr("udp", d.extServer+":22025")
+	extIP, err := net.ResolveUDPAddr("udp", d.extServer)
 	if err != nil {
 		log.Printf("discover/external: %v; no external announcements", err)
 		return
 	}
 
-	buf := EncodePacket(Packet{AnnouncementMagic, uint16(d.ExtListenPort), d.MyID, nil})
+	buf := EncodePacket(Packet{AnnouncementMagic, uint16(22000), d.MyID, nil})
 	go d.writeAnnouncements(buf, extIP, d.ExtBroadcastIntv)
 }
 
@@ -213,7 +211,7 @@ func (d *Discoverer) recvAnnouncements() {
 }
 
 func (d *Discoverer) externalLookup(node string) (string, bool) {
-	extIP, err := net.ResolveUDPAddr("udp", d.extServer+":22025")
+	extIP, err := net.ResolveUDPAddr("udp", d.extServer)
 	if err != nil {
 		log.Printf("discover/external: %v; no external lookup", err)
 		return "", false

gui.go

@@ -3,17 +3,18 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"io"
 	"log"
 	"mime"
 	"net/http"
 	"path/filepath"
 	"runtime"
 	"sync"
+	"time"
 
-	"bitbucket.org/tebeka/nrsc"
+	"github.com/calmh/syncthing/auto"
 	"github.com/calmh/syncthing/model"
 	"github.com/codegangsta/martini"
+	"github.com/cratonica/embed"
 )
 
 func startGUI(addr string, m *model.Model) {
@@ -26,9 +27,14 @@ func startGUI(addr string, m *model.Model) {
 	router.Get("/rest/need", restGetNeed)
 	router.Get("/rest/system", restGetSystem)
 
+	fs, err := embed.Unpack(auto.Resources)
+	if err != nil {
+		panic(err)
+	}
+
 	go func() {
 		mr := martini.New()
-		mr.Use(nrscStatic("gui"))
+		mr.Use(embeddedStatic(fs))
 		mr.Use(martini.Recovery())
 		mr.Action(router.Handle)
 		mr.Map(m)
@@ -75,6 +81,7 @@ func restGetConnections(m *model.Model, w http.ResponseWriter) {
 
 func restGetConfig(w http.ResponseWriter) {
 	var res = make(map[string]interface{})
+	res["myID"] = myID
 	res["repository"] = config.OptionMap("repository")
 	res["nodes"] = config.OptionMap("nodes")
 	w.Header().Set("Content-Type", "application/json")
@@ -123,36 +130,28 @@ func restGetSystem(w http.ResponseWriter) {
 	json.NewEncoder(w).Encode(res)
 }
 
-func nrscStatic(path string) interface{} {
-	if err := nrsc.Initialize(); err != nil {
-		panic("Unable to initialize nrsc: " + err.Error())
-	}
+func embeddedStatic(fs map[string][]byte) interface{} {
+	var modt = time.Now().UTC().Format(http.TimeFormat)
+
 	return func(res http.ResponseWriter, req *http.Request, log *log.Logger) {
 		file := req.URL.Path
 
-		// nrsc expects there not to be a leading slash
 		if file[0] == '/' {
 			file = file[1:]
 		}
 
-		f := nrsc.Get(file)
-		if f == nil {
+		bs, ok := fs[file]
+		if !ok {
 			return
 		}
 
-		rdr, err := f.Open()
-		if err != nil {
-			http.Error(res, "Internal Server Error", http.StatusInternalServerError)
-		}
-		defer rdr.Close()
-
 		mtype := mime.TypeByExtension(filepath.Ext(req.URL.Path))
 		if len(mtype) != 0 {
 			res.Header().Set("Content-Type", mtype)
 		}
-		res.Header().Set("Content-Size", fmt.Sprintf("%d", f.Size()))
-		res.Header().Set("Last-Modified", f.ModTime().UTC().Format(http.TimeFormat))
+		res.Header().Set("Content-Size", fmt.Sprintf("%d", len(bs)))
+		res.Header().Set("Last-Modified", modt)
 
-		io.Copy(res, rdr)
+		res.Write(bs)
 	}
 }

gui/bootstrap/css/bootstrap-theme.css

@@ -1,397 +0,0 @@
-/*!
- * Bootstrap v3.0.3 (http://getbootstrap.com)
- * Copyright 2013 Twitter, Inc.
- * Licensed under http://www.apache.org/licenses/LICENSE-2.0
- */
-
-.btn-default,
-.btn-primary,
-.btn-success,
-.btn-info,
-.btn-warning,
-.btn-danger {
-  text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.2);
-  -webkit-box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.15), 0 1px 1px rgba(0, 0, 0, 0.075);
-          box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.15), 0 1px 1px rgba(0, 0, 0, 0.075);
-}
-
-.btn-default:active,
-.btn-primary:active,
-.btn-success:active,
-.btn-info:active,
-.btn-warning:active,
-.btn-danger:active,
-.btn-default.active,
-.btn-primary.active,
-.btn-success.active,
-.btn-info.active,
-.btn-warning.active,
-.btn-danger.active {
-  -webkit-box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
-          box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
-}
-
-.btn:active,
-.btn.active {
-  background-image: none;
-}
-
-.btn-default {
-  text-shadow: 0 1px 0 #fff;
-  background-image: -webkit-linear-gradient(top, #ffffff 0%, #e0e0e0 100%);
-  background-image: linear-gradient(to bottom, #ffffff 0%, #e0e0e0 100%);
-  background-repeat: repeat-x;
-  border-color: #dbdbdb;
-  border-color: #ccc;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffffffff', endColorstr='#ffe0e0e0', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.btn-default:hover,
-.btn-default:focus {
-  background-color: #e0e0e0;
-  background-position: 0 -15px;
-}
-
-.btn-default:active,
-.btn-default.active {
-  background-color: #e0e0e0;
-  border-color: #dbdbdb;
-}
-
-.btn-primary {
-  background-image: -webkit-linear-gradient(top, #428bca 0%, #2d6ca2 100%);
-  background-image: linear-gradient(to bottom, #428bca 0%, #2d6ca2 100%);
-  background-repeat: repeat-x;
-  border-color: #2b669a;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff428bca', endColorstr='#ff2d6ca2', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.btn-primary:hover,
-.btn-primary:focus {
-  background-color: #2d6ca2;
-  background-position: 0 -15px;
-}
-
-.btn-primary:active,
-.btn-primary.active {
-  background-color: #2d6ca2;
-  border-color: #2b669a;
-}
-
-.btn-success {
-  background-image: -webkit-linear-gradient(top, #5cb85c 0%, #419641 100%);
-  background-image: linear-gradient(to bottom, #5cb85c 0%, #419641 100%);
-  background-repeat: repeat-x;
-  border-color: #3e8f3e;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff5cb85c', endColorstr='#ff419641', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.btn-success:hover,
-.btn-success:focus {
-  background-color: #419641;
-  background-position: 0 -15px;
-}
-
-.btn-success:active,
-.btn-success.active {
-  background-color: #419641;
-  border-color: #3e8f3e;
-}
-
-.btn-warning {
-  background-image: -webkit-linear-gradient(top, #f0ad4e 0%, #eb9316 100%);
-  background-image: linear-gradient(to bottom, #f0ad4e 0%, #eb9316 100%);
-  background-repeat: repeat-x;
-  border-color: #e38d13;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff0ad4e', endColorstr='#ffeb9316', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.btn-warning:hover,
-.btn-warning:focus {
-  background-color: #eb9316;
-  background-position: 0 -15px;
-}
-
-.btn-warning:active,
-.btn-warning.active {
-  background-color: #eb9316;
-  border-color: #e38d13;
-}
-
-.btn-danger {
-  background-image: -webkit-linear-gradient(top, #d9534f 0%, #c12e2a 100%);
-  background-image: linear-gradient(to bottom, #d9534f 0%, #c12e2a 100%);
-  background-repeat: repeat-x;
-  border-color: #b92c28;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffd9534f', endColorstr='#ffc12e2a', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.btn-danger:hover,
-.btn-danger:focus {
-  background-color: #c12e2a;
-  background-position: 0 -15px;
-}
-
-.btn-danger:active,
-.btn-danger.active {
-  background-color: #c12e2a;
-  border-color: #b92c28;
-}
-
-.btn-info {
-  background-image: -webkit-linear-gradient(top, #5bc0de 0%, #2aabd2 100%);
-  background-image: linear-gradient(to bottom, #5bc0de 0%, #2aabd2 100%);
-  background-repeat: repeat-x;
-  border-color: #28a4c9;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff5bc0de', endColorstr='#ff2aabd2', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.btn-info:hover,
-.btn-info:focus {
-  background-color: #2aabd2;
-  background-position: 0 -15px;
-}
-
-.btn-info:active,
-.btn-info.active {
-  background-color: #2aabd2;
-  border-color: #28a4c9;
-}
-
-.thumbnail,
-.img-thumbnail {
-  -webkit-box-shadow: 0 1px 2px rgba(0, 0, 0, 0.075);
-          box-shadow: 0 1px 2px rgba(0, 0, 0, 0.075);
-}
-
-.dropdown-menu > li > a:hover,
-.dropdown-menu > li > a:focus {
-  background-color: #e8e8e8;
-  background-image: -webkit-linear-gradient(top, #f5f5f5 0%, #e8e8e8 100%);
-  background-image: linear-gradient(to bottom, #f5f5f5 0%, #e8e8e8 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff5f5f5', endColorstr='#ffe8e8e8', GradientType=0);
-}
-
-.dropdown-menu > .active > a,
-.dropdown-menu > .active > a:hover,
-.dropdown-menu > .active > a:focus {
-  background-color: #357ebd;
-  background-image: -webkit-linear-gradient(top, #428bca 0%, #357ebd 100%);
-  background-image: linear-gradient(to bottom, #428bca 0%, #357ebd 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff428bca', endColorstr='#ff357ebd', GradientType=0);
-}
-
-.navbar-default {
-  background-image: -webkit-linear-gradient(top, #ffffff 0%, #f8f8f8 100%);
-  background-image: linear-gradient(to bottom, #ffffff 0%, #f8f8f8 100%);
-  background-repeat: repeat-x;
-  border-radius: 4px;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffffffff', endColorstr='#fff8f8f8', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-  -webkit-box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.15), 0 1px 5px rgba(0, 0, 0, 0.075);
-          box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.15), 0 1px 5px rgba(0, 0, 0, 0.075);
-}
-
-.navbar-default .navbar-nav > .active > a {
-  background-image: -webkit-linear-gradient(top, #ebebeb 0%, #f3f3f3 100%);
-  background-image: linear-gradient(to bottom, #ebebeb 0%, #f3f3f3 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffebebeb', endColorstr='#fff3f3f3', GradientType=0);
-  -webkit-box-shadow: inset 0 3px 9px rgba(0, 0, 0, 0.075);
-          box-shadow: inset 0 3px 9px rgba(0, 0, 0, 0.075);
-}
-
-.navbar-brand,
-.navbar-nav > li > a {
-  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.25);
-}
-
-.navbar-inverse {
-  background-image: -webkit-linear-gradient(top, #3c3c3c 0%, #222222 100%);
-  background-image: linear-gradient(to bottom, #3c3c3c 0%, #222222 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff3c3c3c', endColorstr='#ff222222', GradientType=0);
-  filter: progid:DXImageTransform.Microsoft.gradient(enabled=false);
-}
-
-.navbar-inverse .navbar-nav > .active > a {
-  background-image: -webkit-linear-gradient(top, #222222 0%, #282828 100%);
-  background-image: linear-gradient(to bottom, #222222 0%, #282828 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff222222', endColorstr='#ff282828', GradientType=0);
-  -webkit-box-shadow: inset 0 3px 9px rgba(0, 0, 0, 0.25);
-          box-shadow: inset 0 3px 9px rgba(0, 0, 0, 0.25);
-}
-
-.navbar-inverse .navbar-brand,
-.navbar-inverse .navbar-nav > li > a {
-  text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.25);
-}
-
-.navbar-static-top,
-.navbar-fixed-top,
-.navbar-fixed-bottom {
-  border-radius: 0;
-}
-
-.alert {
-  text-shadow: 0 1px 0 rgba(255, 255, 255, 0.2);
-  -webkit-box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.25), 0 1px 2px rgba(0, 0, 0, 0.05);
-          box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.25), 0 1px 2px rgba(0, 0, 0, 0.05);
-}
-
-.alert-success {
-  background-image: -webkit-linear-gradient(top, #dff0d8 0%, #c8e5bc 100%);
-  background-image: linear-gradient(to bottom, #dff0d8 0%, #c8e5bc 100%);
-  background-repeat: repeat-x;
-  border-color: #b2dba1;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffdff0d8', endColorstr='#ffc8e5bc', GradientType=0);
-}
-
-.alert-info {
-  background-image: -webkit-linear-gradient(top, #d9edf7 0%, #b9def0 100%);
-  background-image: linear-gradient(to bottom, #d9edf7 0%, #b9def0 100%);
-  background-repeat: repeat-x;
-  border-color: #9acfea;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffd9edf7', endColorstr='#ffb9def0', GradientType=0);
-}
-
-.alert-warning {
-  background-image: -webkit-linear-gradient(top, #fcf8e3 0%, #f8efc0 100%);
-  background-image: linear-gradient(to bottom, #fcf8e3 0%, #f8efc0 100%);
-  background-repeat: repeat-x;
-  border-color: #f5e79e;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fffcf8e3', endColorstr='#fff8efc0', GradientType=0);
-}
-
-.alert-danger {
-  background-image: -webkit-linear-gradient(top, #f2dede 0%, #e7c3c3 100%);
-  background-image: linear-gradient(to bottom, #f2dede 0%, #e7c3c3 100%);
-  background-repeat: repeat-x;
-  border-color: #dca7a7;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff2dede', endColorstr='#ffe7c3c3', GradientType=0);
-}
-
-.progress {
-  background-image: -webkit-linear-gradient(top, #ebebeb 0%, #f5f5f5 100%);
-  background-image: linear-gradient(to bottom, #ebebeb 0%, #f5f5f5 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffebebeb', endColorstr='#fff5f5f5', GradientType=0);
-}
-
-.progress-bar {
-  background-image: -webkit-linear-gradient(top, #428bca 0%, #3071a9 100%);
-  background-image: linear-gradient(to bottom, #428bca 0%, #3071a9 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff428bca', endColorstr='#ff3071a9', GradientType=0);
-}
-
-.progress-bar-success {
-  background-image: -webkit-linear-gradient(top, #5cb85c 0%, #449d44 100%);
-  background-image: linear-gradient(to bottom, #5cb85c 0%, #449d44 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff5cb85c', endColorstr='#ff449d44', GradientType=0);
-}
-
-.progress-bar-info {
-  background-image: -webkit-linear-gradient(top, #5bc0de 0%, #31b0d5 100%);
-  background-image: linear-gradient(to bottom, #5bc0de 0%, #31b0d5 100%);
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-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff5bc0de', endColorstr='#ff31b0d5', GradientType=0);
-}
-
-.progress-bar-warning {
-  background-image: -webkit-linear-gradient(top, #f0ad4e 0%, #ec971f 100%);
-  background-image: linear-gradient(to bottom, #f0ad4e 0%, #ec971f 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff0ad4e', endColorstr='#ffec971f', GradientType=0);
-}
-
-.progress-bar-danger {
-  background-image: -webkit-linear-gradient(top, #d9534f 0%, #c9302c 100%);
-  background-image: linear-gradient(to bottom, #d9534f 0%, #c9302c 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffd9534f', endColorstr='#ffc9302c', GradientType=0);
-}
-
-.list-group {
-  border-radius: 4px;
-  -webkit-box-shadow: 0 1px 2px rgba(0, 0, 0, 0.075);
-          box-shadow: 0 1px 2px rgba(0, 0, 0, 0.075);
-}
-
-.list-group-item.active,
-.list-group-item.active:hover,
-.list-group-item.active:focus {
-  text-shadow: 0 -1px 0 #3071a9;
-  background-image: -webkit-linear-gradient(top, #428bca 0%, #3278b3 100%);
-  background-image: linear-gradient(to bottom, #428bca 0%, #3278b3 100%);
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-  border-color: #3278b3;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff428bca', endColorstr='#ff3278b3', GradientType=0);
-}
-
-.panel {
-  -webkit-box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
-          box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
-}
-
-.panel-default > .panel-heading {
-  background-image: -webkit-linear-gradient(top, #f5f5f5 0%, #e8e8e8 100%);
-  background-image: linear-gradient(to bottom, #f5f5f5 0%, #e8e8e8 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff5f5f5', endColorstr='#ffe8e8e8', GradientType=0);
-}
-
-.panel-primary > .panel-heading {
-  background-image: -webkit-linear-gradient(top, #428bca 0%, #357ebd 100%);
-  background-image: linear-gradient(to bottom, #428bca 0%, #357ebd 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ff428bca', endColorstr='#ff357ebd', GradientType=0);
-}
-
-.panel-success > .panel-heading {
-  background-image: -webkit-linear-gradient(top, #dff0d8 0%, #d0e9c6 100%);
-  background-image: linear-gradient(to bottom, #dff0d8 0%, #d0e9c6 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffdff0d8', endColorstr='#ffd0e9c6', GradientType=0);
-}
-
-.panel-info > .panel-heading {
-  background-image: -webkit-linear-gradient(top, #d9edf7 0%, #c4e3f3 100%);
-  background-image: linear-gradient(to bottom, #d9edf7 0%, #c4e3f3 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffd9edf7', endColorstr='#ffc4e3f3', GradientType=0);
-}
-
-.panel-warning > .panel-heading {
-  background-image: -webkit-linear-gradient(top, #fcf8e3 0%, #faf2cc 100%);
-  background-image: linear-gradient(to bottom, #fcf8e3 0%, #faf2cc 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fffcf8e3', endColorstr='#fffaf2cc', GradientType=0);
-}
-
-.panel-danger > .panel-heading {
-  background-image: -webkit-linear-gradient(top, #f2dede 0%, #ebcccc 100%);
-  background-image: linear-gradient(to bottom, #f2dede 0%, #ebcccc 100%);
-  background-repeat: repeat-x;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#fff2dede', endColorstr='#ffebcccc', GradientType=0);
-}
-
-.well {
-  background-image: -webkit-linear-gradient(top, #e8e8e8 0%, #f5f5f5 100%);
-  background-image: linear-gradient(to bottom, #e8e8e8 0%, #f5f5f5 100%);
-  background-repeat: repeat-x;
-  border-color: #dcdcdc;
-  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffe8e8e8', endColorstr='#fff5f5f5', GradientType=0);
-  -webkit-box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.05), 0 1px 0 rgba(255, 255, 255, 0.1);
-          box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.05), 0 1px 0 rgba(255, 255, 255, 0.1);
-}

gui/index.html

@@ -9,7 +9,7 @@
 <link rel="shortcut icon" href="../../docs-assets/ico/favicon.png">
 
 <title>syncthing</title>
-<link href="bootstrap/css/bootstrap.css" rel="stylesheet">
+<link href="bootstrap/css/bootstrap.min.css" rel="stylesheet">
 <style type="text/css">
 html, body {
     height: 100%;
@@ -54,7 +54,7 @@ html, body {
                             <div class="progress-bar" role="progressbar" aria-valuenow="60" aria-valuemin="0" aria-valuemax="100"
                                 ng-class="{'progress-bar-success': model.needBytes === 0, 'progress-bar-info': model.needBytes !== 0}"
                                 style="width: {{100 * model.inSyncBytes / model.globalBytes | number:2}}%;">
-                                 {{100 * model.inSyncBytes / model.globalBytes | alwaysNumber | number:0}}%
+                                {{100 * model.inSyncBytes / model.globalBytes | alwaysNumber | number:0}}%
                             </div>
                         </div>
                         <p ng-show="model.needBytes > 0">Need {{model.needFiles | alwaysNumber}} files, {{model.needBytes | binary}}B</p>
@@ -99,25 +99,37 @@ html, body {
                     <div class="panel-heading"><h3 class="panel-title">Cluster</h3></div>
                     <table class="table table-condensed">
                         <tbody>
-                        <tr ng-repeat="(node, address) in config.nodes" ng-class="{'text-primary': !!connections[node]}">
-                            <td><abbr class="text-monospace" title="{{node}}">{{node | short}}</abbr></td>
+                        <tr ng-repeat="(node, address) in config.nodes" ng-class="{'text-primary': !!connections[node], 'text-muted': node == config.myID}">
+                            <td><span class="text-monospace">{{node | short}}</span></td>
                             <td>
-                                <span ng-show="!!connections[node]">
+                                <span ng-show="node != config.myID">{{connections[node].ClientVersion}}</span>
+                                <span ng-show="node == config.myID">{{version}}</span>
+                            </td>
+                            <td>
+                                <span ng-show="node == config.myID">
+                                    <span class="glyphicon glyphicon-ok"></span>
+                                    (this node)
+                                </span>
+                                <span ng-show="node != config.myID && !!connections[node]">
                                     <span class="glyphicon glyphicon-link"></span>
                                     {{connections[node].Address}}
                                 </span>
-                                <span ng-hide="!!connections[node]">
+                                <span ng-show="node != config.myID && !connections[node]">
                                     <span class="glyphicon glyphicon-cog"></span>
                                     {{address}}
                                 </span>
                             </td>
                             <td class="text-right">
-                                <abbr title="{{connections[node].InBytesTotal | binary}}B">{{connections[node].inbps | metric}}b/s</abbr>
-                                <span class="text-muted glyphicon glyphicon-cloud-download"></span>
+                                <span ng-show="node != config.myID">
+                                    <abbr title="{{connections[node].InBytesTotal | binary}}B">{{connections[node].inbps | metric}}b/s</abbr>
+                                    <span class="text-muted glyphicon glyphicon-cloud-download"></span>
+                                </span>
                             </td>
                             <td class="text-right">
-                                <abbr title="{{connections[node].OutBytesTotal | binary}}B">{{connections[node].outbps | metric}}b/s</abbr>
-                                <span class="text-muted glyphicon glyphicon-cloud-upload"></span>
+                                <span ng-show="node != config.myID">
+                                    <abbr title="{{connections[node].OutBytesTotal | binary}}B">{{connections[node].outbps | metric}}b/s</abbr>
+                                    <span class="text-muted glyphicon glyphicon-cloud-upload"></span>
+                                </span>
                             </td>
                         </tr>
                         </tbody>

gui_unix.go

@@ -1,4 +1,4 @@
-//+build !windows
+//+build !windows,!solaris
 
 package main
 

integration/.gitignore

@@ -0,0 +1,5 @@
+files-*
+conf-*
+md5-*
+genfiles
+md5r

integration/genfiles.go

@@ -0,0 +1,42 @@
+package main
+
+import (
+	"crypto/rand"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	mr "math/rand"
+	"os"
+	"path"
+)
+
+func name() string {
+	var b [16]byte
+	rand.Reader.Read(b[:])
+	return fmt.Sprintf("%x", b[:])
+}
+
+func main() {
+	var files int
+	var maxexp int
+
+	flag.IntVar(&files, "files", 1000, "Number of files")
+	flag.IntVar(&maxexp, "maxexp", 20, "Maximum file size (max = 2^n + 128*1024 B)")
+	flag.Parse()
+
+	for i := 0; i < files; i++ {
+		n := name()
+		p0 := path.Join(string(n[0]), n[0:2])
+		os.MkdirAll(p0, 0755)
+		s := 1 << uint(mr.Intn(maxexp))
+		a := 128 * 1024
+		if a > s {
+			a = s
+		}
+		s += mr.Intn(a)
+		b := make([]byte, s)
+		rand.Reader.Read(b)
+		p1 := path.Join(p0, n)
+		ioutil.WriteFile(p1, b, 0644)
+	}
+}

integration/md5r.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"crypto/md5"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+)
+
+func main() {
+	flag.Parse()
+	args := flag.Args()
+
+	if len(args) == 0 {
+		args = []string{"."}
+	}
+
+	for _, path := range args {
+		err := filepath.Walk(path, walker)
+
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+	}
+}
+
+func walker(path string, info os.FileInfo, err error) error {
+	if err != nil {
+		return err
+	}
+
+	if !info.IsDir() {
+		sum, err := md5file(path)
+		if err != nil {
+			return err
+		}
+		fmt.Printf("%s  %s\n", sum, path)
+	}
+
+	return nil
+}
+
+func md5file(fname string) (hash string, err error) {
+	f, err := os.Open(fname)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+
+	h := md5.New()
+	io.Copy(h, f)
+	hb := h.Sum(nil)
+	hash = fmt.Sprintf("%x", hb)
+
+	return
+}

integration/test.sh

@@ -0,0 +1,74 @@
+#!/bin/bash
+
+rm -rf files-* conf-* md5-*
+
+extraopts=""
+p=$(pwd)
+
+go build genfiles.go
+go build md5r.go
+
+echo "Setting up (keys)..."
+i1=$(syncthing --home conf-1 2>&1 | awk '/My ID/ {print $7}')
+echo $i1
+i2=$(syncthing --home conf-2 2>&1 | awk '/My ID/ {print $7}')
+echo $i2
+i3=$(syncthing --home conf-3 2>&1 | awk '/My ID/ {print $7}')
+echo $i3
+
+echo "Setting up (files)..."
+for i in 1 2 3 ; do
+	cat >conf-$i/syncthing.ini <<EOT
+[repository]
+dir = $p/files-$i
+
+[nodes]
+$i1 = 127.0.0.1:22001
+$i2 = 127.0.0.1:22002
+$i3 = 127.0.0.1:22003
+
+[settings]
+gui-enabled = false
+listen-address = :2200$i
+EOT
+
+	mkdir files-$i
+	pushd files-$i >/dev/null
+	../genfiles -maxexp 21 -files 400
+	touch empty-$i
+	../md5r > ../md5-$i
+	popd >/dev/null
+done
+
+echo "Starting..."
+for i in 1 2 3 ; do
+	sleep 1
+	syncthing --home conf-$i $extraopts &
+done
+
+cat md5-* | sort > md5-tot
+while true ; do
+	read
+	echo Verifying...
+
+	conv=0
+	for i in 1 2 3 ; do
+		pushd files-$i >/dev/null
+		../md5r | sort > ../md5-$i
+		popd >/dev/null
+		if ! cmp md5-$i md5-tot >/dev/null ; then
+			echo $i unconverged
+		else
+			conv=$((conv + 1))
+			echo $i converged
+		fi
+	done
+
+	if [[ $conv == 3 ]] ; then
+		kill %1
+		kill %2
+		kill %3
+		exit
+	fi
+done
+

logger.go

@@ -6,7 +6,8 @@ import (
 	"os"
 )
 
-var logger = log.New(os.Stderr, "", log.Ltime)
+// set in main()
+var logger *log.Logger
 
 func debugln(vals ...interface{}) {
 	s := fmt.Sprintln(vals...)

main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"compress/gzip"
 	"crypto/tls"
+	"flag"
 	"fmt"
 	"log"
 	"net"
@@ -18,48 +19,10 @@ import (
 
 	"github.com/calmh/ini"
 	"github.com/calmh/syncthing/discover"
-	flags "github.com/calmh/syncthing/github.com/jessevdk/go-flags"
 	"github.com/calmh/syncthing/model"
 	"github.com/calmh/syncthing/protocol"
 )
 
-type Options struct {
-	ConfDir     string           `short:"c" long:"cfg" description:"Configuration directory" default:"~/.syncthing" value-name:"DIR"`
-	Listen      string           `short:"l" long:"listen" description:"Listen address" default:":22000" value-name:"ADDR"`
-	ReadOnly    bool             `short:"r" long:"ro" description:"Repository is read only"`
-	Rehash      bool             `long:"rehash" description:"Ignore cache and rehash all files in repository"`
-	NoDelete    bool             `long:"no-delete" description:"Never delete files"`
-	NoSymlinks  bool             `long:"no-symlinks" description:"Don't follow first level symlinks in the repo"`
-	NoStats     bool             `long:"no-stats" description:"Don't print model and connection statistics"`
-	NoGUI       bool             `long:"no-gui" description:"Don't start GUI"`
-	GUIAddr     string           `long:"gui-addr" description:"GUI listen address" default:"127.0.0.1:8080" value-name:"ADDR"`
-	ShowVersion bool             `short:"v" long:"version" description:"Show version"`
-	Discovery   DiscoveryOptions `group:"Discovery Options"`
-	Advanced    AdvancedOptions  `group:"Advanced Options"`
-	Debug       DebugOptions     `group:"Debugging Options"`
-}
-
-type DebugOptions struct {
-	LogSource    bool     `long:"log-source"`
-	TraceModel   []string `long:"trace-model" value-name:"TRACE" description:"idx, net, file, need"`
-	TraceConnect bool     `long:"trace-connect"`
-	Profiler     string   `long:"profiler" value-name:"ADDR"`
-}
-
-type DiscoveryOptions struct {
-	ExternalServer      string `long:"ext-server" description:"External discovery server" value-name:"NAME" default:"syncthing.nym.se"`
-	ExternalPort        int    `short:"e" long:"ext-port" description:"External listen port" value-name:"PORT" default:"22000"`
-	NoExternalDiscovery bool   `short:"n" long:"no-ext-announce" description:"Do not announce presence externally"`
-	NoLocalDiscovery    bool   `short:"N" long:"no-local-announce" description:"Do not announce presence locally"`
-}
-
-type AdvancedOptions struct {
-	RequestsInFlight int           `long:"reqs-in-flight" description:"Parallell in flight requests per file" default:"4" value-name:"REQS"`
-	FilesInFlight    int           `long:"files-in-flight" description:"Parallell in flight file pulls" default:"8" value-name:"FILES"`
-	ScanInterval     time.Duration `long:"scan-intv" description:"Repository scan interval" default:"60s" value-name:"INTV"`
-	ConnInterval     time.Duration `long:"conn-intv" description:"Node reconnect interval" default:"60s" value-name:"INTV"`
-}
-
 var opts Options
 var Version string = "unknown-dev"
 
@@ -68,17 +31,32 @@ const (
 )
 
 var (
+	myID      string
 	config    ini.Config
 	nodeAddrs = make(map[string][]string)
 )
 
-func main() {
-	_, err := flags.Parse(&opts)
-	if err != nil {
-		fatalln(err)
-	}
+var (
+	showVersion bool
+	showConfig  bool
+	confDir     string
+	trace       string
+	profiler    string
+)
 
-	if opts.ShowVersion {
+func main() {
+	log.SetOutput(os.Stderr)
+	logger = log.New(os.Stderr, "", log.Flags())
+
+	flag.StringVar(&confDir, "home", "~/.syncthing", "Set configuration directory")
+	flag.BoolVar(&showConfig, "config", false, "Print current configuration")
+	flag.StringVar(&trace, "debug.trace", "", "(connect,net,idx,file,pull)")
+	flag.StringVar(&profiler, "debug.profiler", "", "(addr)")
+	flag.BoolVar(&showVersion, "version", false, "Show version")
+	flag.Usage = usageFor(flag.CommandLine, "syncthing [options]")
+	flag.Parse()
+
+	if showVersion {
 		fmt.Println(Version)
 		os.Exit(0)
 	}
@@ -91,29 +69,73 @@ func main() {
 		runtime.GOMAXPROCS(runtime.NumCPU())
 	}
 
-	if len(opts.Debug.TraceModel) > 0 || opts.Debug.LogSource {
-		logger = log.New(os.Stderr, "", log.Lshortfile|log.Ldate|log.Ltime|log.Lmicroseconds)
+	if len(trace) > 0 {
+		log.SetFlags(log.Lshortfile | log.Ldate | log.Ltime | log.Lmicroseconds)
+		logger.SetFlags(log.Lshortfile | log.Ldate | log.Ltime | log.Lmicroseconds)
 	}
-	opts.ConfDir = expandTilde(opts.ConfDir)
-
-	infoln("Version", Version)
+	confDir = expandTilde(confDir)
 
 	// Ensure that our home directory exists and that we have a certificate and key.
 
-	ensureDir(opts.ConfDir, 0700)
-	cert, err := loadCert(opts.ConfDir)
+	ensureDir(confDir, 0700)
+	cert, err := loadCert(confDir)
 	if err != nil {
-		newCertificate(opts.ConfDir)
-		cert, err = loadCert(opts.ConfDir)
+		newCertificate(confDir)
+		cert, err = loadCert(confDir)
 		fatalErr(err)
 	}
 
-	myID := string(certId(cert.Certificate[0]))
+	myID = string(certId(cert.Certificate[0]))
+	log.SetPrefix("[" + myID[0:5] + "] ")
+	logger.SetPrefix("[" + myID[0:5] + "] ")
+
+	// Load the configuration file, if it exists.
+	// If it does not, create a template.
+
+	cfgFile := path.Join(confDir, confFileName)
+	cf, err := os.Open(cfgFile)
+
+	if err != nil {
+		infoln("My ID:", myID)
+
+		infoln("No config file; creating a template")
+
+		loadConfig(nil, &opts) //loads defaults
+		fd, err := os.Create(cfgFile)
+		if err != nil {
+			fatalln(err)
+		}
+
+		writeConfig(fd, "~/Sync", map[string]string{myID: "dynamic"}, opts, true)
+		fd.Close()
+		infof("Edit %s to suit and restart syncthing.", cfgFile)
+
+		os.Exit(0)
+	}
+
+	config = ini.Parse(cf)
+	cf.Close()
+
+	loadConfig(config.OptionMap("settings"), &opts)
+
+	if showConfig {
+		writeConfig(os.Stdout,
+			config.Get("repository", "dir"),
+			config.OptionMap("nodes"), opts, false)
+		os.Exit(0)
+	}
+
+	infoln("Version", Version)
 	infoln("My ID:", myID)
 
-	if opts.Debug.Profiler != "" {
+	var dir = expandTilde(config.Get("repository", "dir"))
+	if len(dir) == 0 {
+		fatalln("No repository directory. Set dir under [repository] in syncthing.ini.")
+	}
+
+	if len(profiler) > 0 {
 		go func() {
-			err := http.ListenAndServe(opts.Debug.Profiler, nil)
+			err := http.ListenAndServe(profiler, nil)
 			if err != nil {
 				warnln(err)
 			}
@@ -133,18 +155,6 @@ func main() {
 		MinVersion:             tls.VersionTLS12,
 	}
 
-	// Load the configuration file, if it exists.
-
-	cf, err := os.Open(path.Join(opts.ConfDir, confFileName))
-	if err != nil {
-		fatalln("No config file")
-		config = ini.Config{}
-	}
-	config = ini.Parse(cf)
-	cf.Close()
-
-	var dir = expandTilde(config.Get("repository", "dir"))
-
 	// Create a map of desired node connections based on the configuration file
 	// directives.
 
@@ -154,13 +164,16 @@ func main() {
 	}
 
 	ensureDir(dir, -1)
-	m := model.NewModel(dir)
-	for _, t := range opts.Debug.TraceModel {
+	m := model.NewModel(dir, opts.MaxChangeBW*1000)
+	for _, t := range strings.Split(trace, ",") {
 		m.Trace(t)
 	}
+	if opts.LimitRate > 0 {
+		m.LimitRate(opts.LimitRate)
+	}
 
 	// GUI
-	if !opts.NoGUI && opts.GUIAddr != "" {
+	if opts.GUI && opts.GUIAddr != "" {
 		host, port, err := net.SplitHostPort(opts.GUIAddr)
 		if err != nil {
 			warnf("Cannot start GUI on %q: %v", opts.GUIAddr, err)
@@ -177,11 +190,8 @@ func main() {
 	// Walk the repository and update the local model before establishing any
 	// connections to other nodes.
 
-	if !opts.Rehash {
-		infoln("Loading index cache")
-		loadIndex(m)
-	}
 	infoln("Populating repository index")
+	loadIndex(m)
 	updateLocalModel(m)
 
 	// Routine to listen for incoming connections
@@ -195,13 +205,13 @@ func main() {
 	// Routine to pull blocks from other nodes to synchronize the local
 	// repository. Does not run when we are in read only (publish only) mode.
 	if !opts.ReadOnly {
-		if opts.NoDelete {
-			infoln("Deletes from peer nodes will be ignored")
-		} else {
+		if opts.Delete {
 			infoln("Deletes from peer nodes are allowed")
+		} else {
+			infoln("Deletes from peer nodes will be ignored")
 		}
 		okln("Ready to synchronize (read-write)")
-		m.StartRW(!opts.NoDelete, opts.Advanced.FilesInFlight, opts.Advanced.RequestsInFlight)
+		m.StartRW(opts.Delete, opts.ParallelRequests)
 	} else {
 		okln("Ready to synchronize (read only; no external updates accepted)")
 	}
@@ -210,15 +220,15 @@ func main() {
 	// XXX: Should use some fsnotify mechanism.
 	go func() {
 		for {
-			time.Sleep(opts.Advanced.ScanInterval)
-			updateLocalModel(m)
+			time.Sleep(opts.ScanInterval)
+			if m.LocalAge() > opts.ScanInterval.Seconds()/2 {
+				updateLocalModel(m)
+			}
 		}
 	}()
 
-	if !opts.NoStats {
-		// Periodically print statistics
-		go printStatsLoop(m)
-	}
+	// Periodically print statistics
+	go printStatsLoop(m)
 
 	select {}
 }
@@ -236,7 +246,7 @@ func printStatsLoop(m *model.Model) {
 			outbps := 8 * int(float64(stats.OutBytesTotal-lastStats[node].OutBytesTotal)/secs)
 
 			if inbps+outbps > 0 {
-				infof("%s: %sb/s in, %sb/s out", node, MetricPrefix(inbps), MetricPrefix(outbps))
+				infof("%s: %sb/s in, %sb/s out", node[0:5], MetricPrefix(inbps), MetricPrefix(outbps))
 			}
 
 			lastStats[node] = stats
@@ -258,6 +268,11 @@ func listen(myID string, addr string, m *model.Model, cfg *tls.Config) {
 	l, err := tls.Listen("tcp", addr, cfg)
 	fatalErr(err)
 
+	connOpts := map[string]string{
+		"clientId":      "syncthing",
+		"clientVersion": Version,
+	}
+
 listen:
 	for {
 		conn, err := l.Accept()
@@ -266,7 +281,7 @@ listen:
 			continue
 		}
 
-		if opts.Debug.TraceConnect {
+		if strings.Contains(trace, "connect") {
 			debugln("NET: Connect from", conn.RemoteAddr())
 		}
 
@@ -292,7 +307,7 @@ listen:
 
 		for nodeID := range nodeAddrs {
 			if nodeID == remoteID {
-				protoConn := protocol.NewConnection(remoteID, conn, conn, m)
+				protoConn := protocol.NewConnection(remoteID, conn, conn, m, connOpts)
 				m.AddConnection(conn, protoConn)
 				continue listen
 			}
@@ -306,24 +321,29 @@ func connect(myID string, addr string, nodeAddrs map[string][]string, m *model.M
 	fatalErr(err)
 	port, _ := strconv.Atoi(portstr)
 
-	if opts.Discovery.NoLocalDiscovery {
+	if !opts.LocalDiscovery {
 		port = -1
 	} else {
 		infoln("Sending local discovery announcements")
 	}
 
-	if opts.Discovery.NoExternalDiscovery {
-		opts.Discovery.ExternalPort = -1
+	if !opts.ExternalDiscovery {
+		opts.ExternalServer = ""
 	} else {
 		infoln("Sending external discovery announcements")
 	}
 
-	disc, err := discover.NewDiscoverer(myID, port, opts.Discovery.ExternalPort, opts.Discovery.ExternalServer)
+	disc, err := discover.NewDiscoverer(myID, port, opts.ExternalServer)
 
 	if err != nil {
 		warnf("No discovery possible (%v)", err)
 	}
 
+	connOpts := map[string]string{
+		"clientId":      "syncthing",
+		"clientVersion": Version,
+	}
+
 	for {
 	nextNode:
 		for nodeID, addrs := range nodeAddrs {
@@ -344,12 +364,12 @@ func connect(myID string, addr string, nodeAddrs map[string][]string, m *model.M
 					}
 				}
 
-				if opts.Debug.TraceConnect {
+				if strings.Contains(trace, "connect") {
 					debugln("NET: Dial", nodeID, addr)
 				}
 				conn, err := tls.Dial("tcp", addr, cfg)
 				if err != nil {
-					if opts.Debug.TraceConnect {
+					if strings.Contains(trace, "connect") {
 						debugln("NET:", err)
 					}
 					continue
@@ -362,25 +382,25 @@ func connect(myID string, addr string, nodeAddrs map[string][]string, m *model.M
 					continue
 				}
 
-				protoConn := protocol.NewConnection(remoteID, conn, conn, m)
+				protoConn := protocol.NewConnection(remoteID, conn, conn, m, connOpts)
 				m.AddConnection(conn, protoConn)
 				continue nextNode
 			}
 		}
 
-		time.Sleep(opts.Advanced.ConnInterval)
+		time.Sleep(opts.ConnInterval)
 	}
 }
 
 func updateLocalModel(m *model.Model) {
-	files, _ := m.Walk(!opts.NoSymlinks)
+	files, _ := m.Walk(opts.Symlinks)
 	m.ReplaceLocal(files)
 	saveIndex(m)
 }
 
 func saveIndex(m *model.Model) {
 	name := m.RepoID() + ".idx.gz"
-	fullName := path.Join(opts.ConfDir, name)
+	fullName := path.Join(confDir, name)
 	idxf, err := os.Create(fullName + ".tmp")
 	if err != nil {
 		return
@@ -396,7 +416,7 @@ func saveIndex(m *model.Model) {
 
 func loadIndex(m *model.Model) {
 	name := m.RepoID() + ".idx.gz"
-	idxf, err := os.Open(path.Join(opts.ConfDir, name))
+	idxf, err := os.Open(path.Join(confDir, name))
 	if err != nil {
 		return
 	}

model/blocks.go

@@ -7,15 +7,15 @@ import (
 )
 
 type Block struct {
-	Offset uint64
-	Length uint32
+	Offset int64
+	Size   uint32
 	Hash   []byte
 }
 
 // Blocks returns the blockwise hash of the reader.
 func Blocks(r io.Reader, blocksize int) ([]Block, error) {
 	var blocks []Block
-	var offset uint64
+	var offset int64
 	for {
 		lr := &io.LimitedReader{r, int64(blocksize)}
 		hf := sha256.New()
@@ -30,11 +30,20 @@ func Blocks(r io.Reader, blocksize int) ([]Block, error) {
 
 		b := Block{
 			Offset: offset,
-			Length: uint32(n),
+			Size:   uint32(n),
 			Hash:   hf.Sum(nil),
 		}
 		blocks = append(blocks, b)
-		offset += uint64(n)
+		offset += int64(n)
+	}
+
+	if len(blocks) == 0 {
+		// Empty file
+		blocks = append(blocks, Block{
+			Offset: 0,
+			Size:   0,
+			Hash:   []uint8{0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14, 0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9, 0x24, 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c, 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55},
+		})
 	}
 
 	return blocks, nil

model/blocks_test.go

@@ -11,7 +11,8 @@ var blocksTestData = []struct {
 	blocksize int
 	hash      []string
 }{
-	{[]byte(""), 1024, []string{}},
+	{[]byte(""), 1024, []string{
+		"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"}},
 	{[]byte("contents"), 1024, []string{
 		"d1b2a59fbea7e20077af9f91b27e95e865061b270be03ff539ab3b73587882e8"}},
 	{[]byte("contents"), 9, []string{
@@ -52,7 +53,7 @@ func TestBlocks(t *testing.T) {
 			t.Fatalf("Incorrect number of blocks %d != %d", l, len(test.hash))
 		} else {
 			i := 0
-			for off := uint64(0); off < uint64(len(test.data)); off += uint64(test.blocksize) {
+			for off := int64(0); off < int64(len(test.data)); off += int64(test.blocksize) {
 				if blocks[i].Offset != off {
 					t.Errorf("Incorrect offset for block %d: %d != %d", i, blocks[i].Offset, off)
 				}
@@ -61,8 +62,8 @@ func TestBlocks(t *testing.T) {
 				if rem := len(test.data) - int(off); bs > rem {
 					bs = rem
 				}
-				if int(blocks[i].Length) != bs {
-					t.Errorf("Incorrect length for block %d: %d != %d", i, blocks[i].Length, bs)
+				if int(blocks[i].Size) != bs {
+					t.Errorf("Incorrect length for block %d: %d != %d", i, blocks[i].Size, bs)
 				}
 				if h := fmt.Sprintf("%x", blocks[i].Hash); h != test.hash[i] {
 					t.Errorf("Incorrect block hash %q != %q", h, test.hash[i])
@@ -86,7 +87,7 @@ var diffTestData = []struct {
 	{"contents", "cantents", 3, []Block{{0, 3, nil}}},
 	{"contents", "contants", 3, []Block{{3, 3, nil}}},
 	{"contents", "cantants", 3, []Block{{0, 3, nil}, {3, 3, nil}}},
-	{"contents", "", 3, nil},
+	{"contents", "", 3, []Block{{0, 0, nil}}},
 	{"", "contents", 3, []Block{{0, 3, nil}, {3, 3, nil}, {6, 2, nil}}},
 	{"con", "contents", 3, []Block{{3, 3, nil}, {6, 2, nil}}},
 	{"contents", "con", 3, nil},
@@ -106,8 +107,8 @@ func TestDiff(t *testing.T) {
 				if d[j].Offset != test.d[j].Offset {
 					t.Errorf("Incorrect offset for diff %d block %d; %d != %d", i, j, d[j].Offset, test.d[j].Offset)
 				}
-				if d[j].Length != test.d[j].Length {
-					t.Errorf("Incorrect length for diff %d block %d; %d != %d", i, j, d[j].Length, test.d[j].Length)
+				if d[j].Size != test.d[j].Size {
+					t.Errorf("Incorrect length for diff %d block %d; %d != %d", i, j, d[j].Size, test.d[j].Size)
 				}
 			}
 		}

model/filemonitor.go

@@ -0,0 +1,173 @@
+package model
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"log"
+	"os"
+	"path"
+	"sync"
+	"time"
+
+	"github.com/calmh/syncthing/buffers"
+)
+
+type fileMonitor struct {
+	name        string // in-repo name
+	path        string // full path
+	writeDone   sync.WaitGroup
+	model       *Model
+	global      File
+	localBlocks []Block
+	copyError   error
+	writeError  error
+}
+
+func (m *fileMonitor) FileBegins(cc <-chan content) error {
+	if m.model.trace["file"] {
+		log.Printf("FILE: FileBegins: " + m.name)
+	}
+
+	tmp := tempName(m.path, m.global.Modified)
+
+	dir := path.Dir(tmp)
+	_, err := os.Stat(dir)
+	if err != nil && os.IsNotExist(err) {
+		err = os.MkdirAll(dir, 0777)
+		if err != nil {
+			return err
+		}
+	}
+
+	outFile, err := os.Create(tmp)
+	if err != nil {
+		return err
+	}
+
+	m.writeDone.Add(1)
+
+	var writeWg sync.WaitGroup
+	if len(m.localBlocks) > 0 {
+		writeWg.Add(1)
+		inFile, err := os.Open(m.path)
+		if err != nil {
+			return err
+		}
+
+		// Copy local blocks, close infile when done
+		go m.copyLocalBlocks(inFile, outFile, &writeWg)
+	}
+
+	// Write remote blocks,
+	writeWg.Add(1)
+	go m.copyRemoteBlocks(cc, outFile, &writeWg)
+
+	// Wait for both writing routines, then close the outfile
+	go func() {
+		writeWg.Wait()
+		outFile.Close()
+		m.writeDone.Done()
+	}()
+
+	return nil
+}
+
+func (m *fileMonitor) copyLocalBlocks(inFile, outFile *os.File, writeWg *sync.WaitGroup) {
+	defer inFile.Close()
+	defer writeWg.Done()
+
+	var buf = buffers.Get(BlockSize)
+	defer buffers.Put(buf)
+
+	for _, lb := range m.localBlocks {
+		buf = buf[:lb.Size]
+		_, err := inFile.ReadAt(buf, lb.Offset)
+		if err != nil {
+			m.copyError = err
+			return
+		}
+		_, err = outFile.WriteAt(buf, lb.Offset)
+		if err != nil {
+			m.copyError = err
+			return
+		}
+	}
+}
+
+func (m *fileMonitor) copyRemoteBlocks(cc <-chan content, outFile *os.File, writeWg *sync.WaitGroup) {
+	defer writeWg.Done()
+
+	for content := range cc {
+		_, err := outFile.WriteAt(content.data, content.offset)
+		buffers.Put(content.data)
+		if err != nil {
+			m.writeError = err
+			return
+		}
+	}
+}
+
+func (m *fileMonitor) FileDone() error {
+	if m.model.trace["file"] {
+		log.Printf("FILE: FileDone: " + m.name)
+	}
+
+	m.writeDone.Wait()
+
+	tmp := tempName(m.path, m.global.Modified)
+	defer os.Remove(tmp)
+
+	if m.copyError != nil {
+		return m.copyError
+	}
+	if m.writeError != nil {
+		return m.writeError
+	}
+
+	err := hashCheck(tmp, m.global.Blocks)
+	if err != nil {
+		return err
+	}
+
+	err = os.Chtimes(tmp, time.Unix(m.global.Modified, 0), time.Unix(m.global.Modified, 0))
+	if err != nil {
+		return err
+	}
+
+	err = os.Chmod(tmp, os.FileMode(m.global.Flags&0777))
+	if err != nil {
+		return err
+	}
+
+	err = os.Rename(tmp, m.path)
+	if err != nil {
+		return err
+	}
+
+	m.model.updateLocal(m.global)
+	return nil
+}
+
+func hashCheck(name string, correct []Block) error {
+	rf, err := os.Open(name)
+	if err != nil {
+		return err
+	}
+	defer rf.Close()
+
+	current, err := Blocks(rf, BlockSize)
+	if err != nil {
+		return err
+	}
+	if len(current) != len(correct) {
+		return errors.New("incorrect number of blocks")
+	}
+	for i := range current {
+		if bytes.Compare(current[i].Hash, correct[i].Hash) != 0 {
+			return fmt.Errorf("hash mismatch: %x != %x", current[i], correct[i])
+		}
+	}
+
+	return nil
+}

model/filequeue.go

@@ -0,0 +1,236 @@
+package model
+
+import (
+	"log"
+	"sort"
+	"sync"
+	"time"
+)
+
+type Monitor interface {
+	FileBegins(<-chan content) error
+	FileDone() error
+}
+
+type FileQueue struct {
+	files        queuedFileList
+	sorted       bool
+	fmut         sync.Mutex // protects files and sorted
+	availability map[string][]string
+	amut         sync.Mutex // protects availability
+	queued       map[string]bool
+}
+
+type queuedFile struct {
+	name         string
+	blocks       []Block
+	activeBlocks []bool
+	given        int
+	remaining    int
+	channel      chan content
+	nodes        []string
+	nodesChecked time.Time
+	monitor      Monitor
+}
+
+type content struct {
+	offset int64
+	data   []byte
+}
+
+type queuedFileList []queuedFile
+
+func (l queuedFileList) Len() int { return len(l) }
+
+func (l queuedFileList) Swap(a, b int) { l[a], l[b] = l[b], l[a] }
+
+func (l queuedFileList) Less(a, b int) bool {
+	// Sort by most blocks already given out, then alphabetically
+	if l[a].given != l[b].given {
+		return l[a].given > l[b].given
+	}
+	return l[a].name < l[b].name
+}
+
+type queuedBlock struct {
+	name  string
+	block Block
+	index int
+}
+
+func NewFileQueue() *FileQueue {
+	return &FileQueue{
+		availability: make(map[string][]string),
+		queued:       make(map[string]bool),
+	}
+}
+
+func (q *FileQueue) Add(name string, blocks []Block, monitor Monitor) {
+	q.fmut.Lock()
+	defer q.fmut.Unlock()
+
+	if q.queued[name] {
+		return
+	}
+
+	q.files = append(q.files, queuedFile{
+		name:         name,
+		blocks:       blocks,
+		activeBlocks: make([]bool, len(blocks)),
+		remaining:    len(blocks),
+		channel:      make(chan content),
+		monitor:      monitor,
+	})
+	q.queued[name] = true
+	q.sorted = false
+}
+
+func (q *FileQueue) Len() int {
+	q.fmut.Lock()
+	defer q.fmut.Unlock()
+
+	return len(q.files)
+}
+
+func (q *FileQueue) Get(nodeID string) (queuedBlock, bool) {
+	q.fmut.Lock()
+	defer q.fmut.Unlock()
+
+	if !q.sorted {
+		sort.Sort(q.files)
+		q.sorted = true
+	}
+
+	for i := range q.files {
+		qf := &q.files[i]
+
+		q.amut.Lock()
+		av := q.availability[qf.name]
+		q.amut.Unlock()
+
+		if len(av) == 0 {
+			// Noone has the file we want; abort.
+			if qf.remaining != len(qf.blocks) {
+				// We have already started on this file; close it down
+				close(qf.channel)
+				if mon := qf.monitor; mon != nil {
+					mon.FileDone()
+				}
+			}
+			delete(q.queued, qf.name)
+			q.deleteAt(i)
+			return queuedBlock{}, false
+		}
+
+		for _, ni := range av {
+			// Find and return the next block in the queue
+			if ni == nodeID {
+				for j, b := range qf.blocks {
+					if !qf.activeBlocks[j] {
+						qf.activeBlocks[j] = true
+						qf.given++
+						return queuedBlock{
+							name:  qf.name,
+							block: b,
+							index: j,
+						}, true
+					}
+				}
+				break
+			}
+		}
+	}
+
+	// We found nothing to do
+	return queuedBlock{}, false
+}
+
+func (q *FileQueue) Done(file string, offset int64, data []byte) {
+	q.fmut.Lock()
+	defer q.fmut.Unlock()
+
+	c := content{
+		offset: offset,
+		data:   data,
+	}
+	for i := range q.files {
+		qf := &q.files[i]
+
+		if qf.name == file {
+			if qf.monitor != nil && qf.remaining == len(qf.blocks) {
+				err := qf.monitor.FileBegins(qf.channel)
+				if err != nil {
+					log.Printf("WARNING: %s: %v (not synced)", qf.name, err)
+					delete(q.queued, qf.name)
+					q.deleteAt(i)
+					return
+				}
+			}
+
+			qf.channel <- c
+			qf.remaining--
+
+			if qf.remaining == 0 {
+				close(qf.channel)
+				if qf.monitor != nil {
+					err := qf.monitor.FileDone()
+					if err != nil {
+						log.Printf("WARNING: %s: %v", qf.name, err)
+					}
+				}
+				delete(q.queued, qf.name)
+				q.deleteAt(i)
+			}
+			return
+		}
+	}
+	panic("unreachable")
+}
+
+func (q *FileQueue) QueuedFiles() (files []string) {
+	q.fmut.Lock()
+	defer q.fmut.Unlock()
+
+	for _, qf := range q.files {
+		files = append(files, qf.name)
+	}
+	return
+}
+
+func (q *FileQueue) deleteAt(i int) {
+	q.files = q.files[:i+copy(q.files[i:], q.files[i+1:])]
+}
+
+func (q *FileQueue) deleteFile(n string) {
+	for i, file := range q.files {
+		if n == file.name {
+			q.deleteAt(i)
+			delete(q.queued, file.name)
+			return
+		}
+	}
+}
+
+func (q *FileQueue) SetAvailable(file string, nodes []string) {
+	q.amut.Lock()
+	defer q.amut.Unlock()
+
+	q.availability[file] = nodes
+}
+
+func (q *FileQueue) RemoveAvailable(toRemove string) {
+	q.amut.Lock()
+	defer q.amut.Unlock()
+
+	for file, nodes := range q.availability {
+		for i, node := range nodes {
+			if node == toRemove {
+				q.availability[file] = nodes[:i+copy(nodes[i:], nodes[i+1:])]
+				if len(q.availability[file]) == 0 {
+					q.deleteFile(file)
+				}
+			}
+			break
+		}
+	}
+}

model/filequeue_test.go

@@ -0,0 +1,277 @@
+package model
+
+import (
+	"reflect"
+	"sync"
+	"sync/atomic"
+	"testing"
+)
+
+func TestFileQueueAdd(t *testing.T) {
+	q := NewFileQueue()
+	q.Add("foo", nil, nil)
+}
+
+func TestFileQueueAddSorting(t *testing.T) {
+	q := NewFileQueue()
+	q.SetAvailable("zzz", []string{"nodeID"})
+	q.SetAvailable("aaa", []string{"nodeID"})
+
+	q.Add("zzz", []Block{{Offset: 0, Size: 128}, {Offset: 128, Size: 128}}, nil)
+	q.Add("aaa", []Block{{Offset: 0, Size: 128}, {Offset: 128, Size: 128}}, nil)
+	b, _ := q.Get("nodeID")
+	if b.name != "aaa" {
+		t.Errorf("Incorrectly sorted get: %+v", b)
+	}
+
+	q = NewFileQueue()
+	q.SetAvailable("zzz", []string{"nodeID"})
+	q.SetAvailable("aaa", []string{"nodeID"})
+
+	q.Add("zzz", []Block{{Offset: 0, Size: 128}, {Offset: 128, Size: 128}}, nil)
+	b, _ = q.Get("nodeID") // Start on zzzz
+	if b.name != "zzz" {
+		t.Errorf("Incorrectly sorted get: %+v", b)
+	}
+	q.Add("aaa", []Block{{Offset: 0, Size: 128}, {Offset: 128, Size: 128}}, nil)
+	b, _ = q.Get("nodeID")
+	if b.name != "zzz" {
+		// Continue rather than starting a new file
+		t.Errorf("Incorrectly sorted get: %+v", b)
+	}
+}
+
+func TestFileQueueLen(t *testing.T) {
+	q := NewFileQueue()
+	q.Add("foo", nil, nil)
+	q.Add("bar", nil, nil)
+
+	if l := q.Len(); l != 2 {
+		t.Errorf("Incorrect len %d != 2 after adds", l)
+	}
+}
+
+func TestFileQueueGet(t *testing.T) {
+	q := NewFileQueue()
+	q.SetAvailable("foo", []string{"nodeID"})
+	q.SetAvailable("bar", []string{"nodeID"})
+
+	q.Add("foo", []Block{
+		{Offset: 0, Size: 128, Hash: []byte("some foo hash bytes")},
+		{Offset: 128, Size: 128, Hash: []byte("some other foo hash bytes")},
+		{Offset: 256, Size: 128, Hash: []byte("more foo hash bytes")},
+	}, nil)
+	q.Add("bar", []Block{
+		{Offset: 0, Size: 128, Hash: []byte("some bar hash bytes")},
+		{Offset: 128, Size: 128, Hash: []byte("some other bar hash bytes")},
+	}, nil)
+
+	// First get should return the first block of the first file
+
+	expected := queuedBlock{
+		name: "bar",
+		block: Block{
+			Offset: 0,
+			Size:   128,
+			Hash:   []byte("some bar hash bytes"),
+		},
+	}
+	actual, ok := q.Get("nodeID")
+
+	if !ok {
+		t.Error("Unexpected non-OK Get()")
+	}
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Incorrect block returned (first)\n  E: %+v\n  A: %+v", expected, actual)
+	}
+
+	// Second get should return the next block of the first file
+
+	expected = queuedBlock{
+		name: "bar",
+		block: Block{
+			Offset: 128,
+			Size:   128,
+			Hash:   []byte("some other bar hash bytes"),
+		},
+		index: 1,
+	}
+	actual, ok = q.Get("nodeID")
+
+	if !ok {
+		t.Error("Unexpected non-OK Get()")
+	}
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Incorrect block returned (second)\n  E: %+v\n  A: %+v", expected, actual)
+	}
+
+	// Third get should return the first block of the second file
+
+	expected = queuedBlock{
+		name: "foo",
+		block: Block{
+			Offset: 0,
+			Size:   128,
+			Hash:   []byte("some foo hash bytes"),
+		},
+	}
+	actual, ok = q.Get("nodeID")
+
+	if !ok {
+		t.Error("Unexpected non-OK Get()")
+	}
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Incorrect block returned (third)\n  E: %+v\n  A: %+v", expected, actual)
+	}
+}
+
+/*
+func TestFileQueueDone(t *testing.T) {
+	ch := make(chan content)
+	var recv sync.WaitGroup
+	recv.Add(1)
+	go func() {
+		content := <-ch
+		if bytes.Compare(content.data, []byte("first block bytes")) != 0 {
+			t.Error("Incorrect data in first content block")
+		}
+
+		content = <-ch
+		if bytes.Compare(content.data, []byte("second block bytes")) != 0 {
+			t.Error("Incorrect data in second content block")
+		}
+
+		_, ok := <-ch
+		if ok {
+			t.Error("Content channel not closed")
+		}
+
+		recv.Done()
+	}()
+
+	q := FileQueue{resolver: fakeResolver{}}
+	q.Add("foo", []Block{
+		{Offset: 0, Length: 128, Hash: []byte("some foo hash bytes")},
+		{Offset: 128, Length: 128, Hash: []byte("some other foo hash bytes")},
+	}, ch)
+
+	b0, _ := q.Get("nodeID")
+	b1, _ := q.Get("nodeID")
+
+	q.Done(b0.name, b0.block.Offset, []byte("first block bytes"))
+	q.Done(b1.name, b1.block.Offset, []byte("second block bytes"))
+
+	recv.Wait()
+
+	// Queue should now have one file less
+
+	if l := q.Len(); l != 0 {
+		t.Error("Queue not empty")
+	}
+
+	_, ok := q.Get("nodeID")
+	if ok {
+		t.Error("Unexpected OK Get()")
+	}
+}
+*/
+
+func TestFileQueueGetNodeIDs(t *testing.T) {
+	q := NewFileQueue()
+	q.SetAvailable("a-foo", []string{"nodeID", "a"})
+	q.SetAvailable("b-bar", []string{"nodeID", "b"})
+
+	q.Add("a-foo", []Block{
+		{Offset: 0, Size: 128, Hash: []byte("some foo hash bytes")},
+		{Offset: 128, Size: 128, Hash: []byte("some other foo hash bytes")},
+		{Offset: 256, Size: 128, Hash: []byte("more foo hash bytes")},
+	}, nil)
+	q.Add("b-bar", []Block{
+		{Offset: 0, Size: 128, Hash: []byte("some bar hash bytes")},
+		{Offset: 128, Size: 128, Hash: []byte("some other bar hash bytes")},
+	}, nil)
+
+	expected := queuedBlock{
+		name: "b-bar",
+		block: Block{
+			Offset: 0,
+			Size:   128,
+			Hash:   []byte("some bar hash bytes"),
+		},
+	}
+	actual, ok := q.Get("b")
+	if !ok {
+		t.Error("Unexpected non-OK Get()")
+	}
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Incorrect block returned\n  E: %+v\n  A: %+v", expected, actual)
+	}
+
+	expected = queuedBlock{
+		name: "a-foo",
+		block: Block{
+			Offset: 0,
+			Size:   128,
+			Hash:   []byte("some foo hash bytes"),
+		},
+	}
+	actual, ok = q.Get("a")
+	if !ok {
+		t.Error("Unexpected non-OK Get()")
+	}
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Incorrect block returned\n  E: %+v\n  A: %+v", expected, actual)
+	}
+
+	expected = queuedBlock{
+		name: "a-foo",
+		block: Block{
+			Offset: 128,
+			Size:   128,
+			Hash:   []byte("some other foo hash bytes"),
+		},
+		index: 1,
+	}
+	actual, ok = q.Get("nodeID")
+	if !ok {
+		t.Error("Unexpected non-OK Get()")
+	}
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Incorrect block returned\n  E: %+v\n  A: %+v", expected, actual)
+	}
+}
+
+func TestFileQueueThreadHandling(t *testing.T) {
+	// This should pass with go test -race
+
+	const n = 100
+	var total int
+	var blocks []Block
+	for i := 1; i <= n; i++ {
+		blocks = append(blocks, Block{Offset: int64(i), Size: 1})
+		total += i
+	}
+
+	q := NewFileQueue()
+	q.Add("foo", blocks, nil)
+	q.SetAvailable("foo", []string{"nodeID"})
+
+	var start = make(chan bool)
+	var gotTot uint32
+	var wg sync.WaitGroup
+	wg.Add(n)
+	for i := 1; i <= n; i++ {
+		go func() {
+			<-start
+			b, _ := q.Get("nodeID")
+			atomic.AddUint32(&gotTot, uint32(b.block.Offset))
+			wg.Done()
+		}()
+	}
+
+	close(start)
+	wg.Wait()
+	if int(gotTot) != total {
+		t.Error("Total mismatch; %d != %d", gotTot, total)
+	}
+}

model/model.go

@@ -1,16 +1,5 @@
 package model
 
-/*
-
-Locking
-=======
-
-The model has read and write locks. These must be acquired as appropriate by
-public methods. To prevent deadlock situations, private methods should never
-acquire locks, but document what locks they require.
-
-*/
-
 import (
 	"crypto/sha1"
 	"errors"
@@ -28,38 +17,49 @@ import (
 )
 
 type Model struct {
-	sync.RWMutex
 	dir string
 
 	global    map[string]File // the latest version of each file as it exists in the cluster
+	gmut      sync.RWMutex    // protects global
 	local     map[string]File // the files we currently have locally on disk
+	lmut      sync.RWMutex    // protects local
 	remote    map[string]map[string]File
-	need      map[string]bool // the files we need to update
+	rmut      sync.RWMutex // protects remote
 	protoConn map[string]Connection
 	rawConn   map[string]io.Closer
+	pmut      sync.RWMutex // protects protoConn and rawConn
 
-	updatedLocal int64 // timestamp of last update to local
-	updateGlobal int64 // timestamp of last update to remote
+	// Queue for files to fetch. fq can call back into the model, so we must ensure
+	// to hold no locks when calling methods on fq.
+	fq *FileQueue
+	dq chan File // queue for files to delete
 
+	updatedLocal        int64 // timestamp of last update to local
+	updateGlobal        int64 // timestamp of last update to remote
 	lastIdxBcast        time.Time
 	lastIdxBcastRequest time.Time
+	umut                sync.RWMutex // provides updated* and lastIdx*
 
-	rwRunning      bool
-	parallellFiles int
-	paralllelReqs  int
-	delete         bool
+	rwRunning bool
+	delete    bool
+	initmut   sync.Mutex // protects rwRunning and delete
 
 	trace map[string]bool
 
-	fileLastChanged   map[string]time.Time
-	fileWasSuppressed map[string]int
+	sup suppressor
+
+	parallelRequests int
+	limitRequestRate chan struct{}
+
+	imut sync.Mutex // protects Index
 }
 
 type Connection interface {
 	ID() string
 	Index([]protocol.FileInfo)
-	Request(name string, offset uint64, size uint32, hash []byte) ([]byte, error)
+	Request(name string, offset int64, size uint32, hash []byte) ([]byte, error)
 	Statistics() protocol.Statistics
+	Option(key string) string
 }
 
 const (
@@ -78,38 +78,51 @@ var (
 // NewModel creates and starts a new model. The model starts in read-only mode,
 // where it sends index information to connected peers and responds to requests
 // for file data without altering the local repository in any way.
-func NewModel(dir string) *Model {
+func NewModel(dir string, maxChangeBw int) *Model {
 	m := &Model{
-		dir:               dir,
-		global:            make(map[string]File),
-		local:             make(map[string]File),
-		remote:            make(map[string]map[string]File),
-		need:              make(map[string]bool),
-		protoConn:         make(map[string]Connection),
-		rawConn:           make(map[string]io.Closer),
-		lastIdxBcast:      time.Now(),
-		trace:             make(map[string]bool),
-		fileLastChanged:   make(map[string]time.Time),
-		fileWasSuppressed: make(map[string]int),
+		dir:          dir,
+		global:       make(map[string]File),
+		local:        make(map[string]File),
+		remote:       make(map[string]map[string]File),
+		protoConn:    make(map[string]Connection),
+		rawConn:      make(map[string]io.Closer),
+		lastIdxBcast: time.Now(),
+		trace:        make(map[string]bool),
+		sup:          suppressor{threshold: int64(maxChangeBw)},
+		fq:           NewFileQueue(),
+		dq:           make(chan File),
 	}
 
 	go m.broadcastIndexLoop()
 	return m
 }
 
+func (m *Model) LimitRate(kbps int) {
+	m.limitRequestRate = make(chan struct{}, kbps)
+	n := kbps/10 + 1
+	go func() {
+		for {
+			time.Sleep(100 * time.Millisecond)
+			for i := 0; i < n; i++ {
+				select {
+				case m.limitRequestRate <- struct{}{}:
+				}
+			}
+		}
+	}()
+}
+
 // Trace enables trace logging of the given facility. This is a debugging function; grep for m.trace.
 func (m *Model) Trace(t string) {
-	m.Lock()
-	defer m.Unlock()
 	m.trace[t] = true
 }
 
 // StartRW starts read/write processing on the current model. When in
 // read/write mode the model will attempt to keep in sync with the cluster by
 // pulling needed files from peer nodes.
-func (m *Model) StartRW(del bool, pfiles, preqs int) {
-	m.Lock()
-	defer m.Unlock()
+func (m *Model) StartRW(del bool, threads int) {
+	m.initmut.Lock()
+	defer m.initmut.Unlock()
 
 	if m.rwRunning {
 		panic("starting started model")
@@ -117,25 +130,35 @@ func (m *Model) StartRW(del bool, pfiles, preqs int) {
 
 	m.rwRunning = true
 	m.delete = del
-	m.parallellFiles = pfiles
-	m.paralllelReqs = preqs
+	m.parallelRequests = threads
 
 	go m.cleanTempFiles()
-	go m.puller()
+	if del {
+		go m.deleteLoop()
+	}
 }
 
 // Generation returns an opaque integer that is guaranteed to increment on
 // every change to the local repository or global model.
 func (m *Model) Generation() int64 {
-	m.RLock()
-	defer m.RUnlock()
+	m.umut.RLock()
+	defer m.umut.RUnlock()
 
 	return m.updatedLocal + m.updateGlobal
 }
 
+func (m *Model) LocalAge() float64 {
+	m.umut.RLock()
+	defer m.umut.RUnlock()
+
+	return time.Since(time.Unix(m.updatedLocal, 0)).Seconds()
+}
+
 type ConnectionInfo struct {
 	protocol.Statistics
-	Address string
+	Address       string
+	ClientID      string
+	ClientVersion string
 }
 
 // ConnectionStats returns a map with connection statistics for each connected node.
@@ -144,27 +167,29 @@ func (m *Model) ConnectionStats() map[string]ConnectionInfo {
 		RemoteAddr() net.Addr
 	}
 
-	m.RLock()
-	defer m.RUnlock()
+	m.pmut.RLock()
 
 	var res = make(map[string]ConnectionInfo)
 	for node, conn := range m.protoConn {
 		ci := ConnectionInfo{
-			Statistics: conn.Statistics(),
+			Statistics:    conn.Statistics(),
+			ClientID:      conn.Option("clientId"),
+			ClientVersion: conn.Option("clientVersion"),
 		}
 		if nc, ok := m.rawConn[node].(remoteAddrer); ok {
 			ci.Address = nc.RemoteAddr().String()
 		}
 		res[node] = ci
 	}
+
+	m.pmut.RUnlock()
 	return res
 }
 
 // LocalSize returns the number of files, deleted files and total bytes for all
 // files in the global model.
 func (m *Model) GlobalSize() (files, deleted, bytes int) {
-	m.RLock()
-	defer m.RUnlock()
+	m.gmut.RLock()
 
 	for _, f := range m.global {
 		if f.Flags&protocol.FlagDeleted == 0 {
@@ -174,14 +199,15 @@ func (m *Model) GlobalSize() (files, deleted, bytes int) {
 			deleted++
 		}
 	}
+
+	m.gmut.RUnlock()
 	return
 }
 
 // LocalSize returns the number of files, deleted files and total bytes for all
 // files in the local repository.
 func (m *Model) LocalSize() (files, deleted, bytes int) {
-	m.RLock()
-	defer m.RUnlock()
+	m.lmut.RLock()
 
 	for _, f := range m.local {
 		if f.Flags&protocol.FlagDeleted == 0 {
@@ -191,14 +217,16 @@ func (m *Model) LocalSize() (files, deleted, bytes int) {
 			deleted++
 		}
 	}
+
+	m.lmut.RUnlock()
 	return
 }
 
 // InSyncSize returns the number and total byte size of the local files that
 // are in sync with the global model.
 func (m *Model) InSyncSize() (files, bytes int) {
-	m.RLock()
-	defer m.RUnlock()
+	m.gmut.RLock()
+	m.lmut.RLock()
 
 	for n, f := range m.local {
 		if gf, ok := m.global[n]; ok && f.Equals(gf) {
@@ -206,67 +234,89 @@ func (m *Model) InSyncSize() (files, bytes int) {
 			bytes += f.Size()
 		}
 	}
+
+	m.lmut.RUnlock()
+	m.gmut.RUnlock()
 	return
 }
 
 // NeedFiles returns the list of currently needed files and the total size.
 func (m *Model) NeedFiles() (files []File, bytes int) {
-	m.RLock()
-	defer m.RUnlock()
+	qf := m.fq.QueuedFiles()
 
-	for n := range m.need {
+	m.gmut.RLock()
+
+	for _, n := range qf {
 		f := m.global[n]
 		files = append(files, f)
 		bytes += f.Size()
 	}
+
+	m.gmut.RUnlock()
 	return
 }
 
 // Index is called when a new node is connected and we receive their full index.
 // Implements the protocol.Model interface.
 func (m *Model) Index(nodeID string, fs []protocol.FileInfo) {
-	m.Lock()
-	defer m.Unlock()
+	var files = make([]File, len(fs))
+	for i := range fs {
+		files[i] = fileFromFileInfo(fs[i])
+	}
+
+	m.imut.Lock()
+	defer m.imut.Unlock()
 
 	if m.trace["net"] {
 		log.Printf("NET IDX(in): %s: %d files", nodeID, len(fs))
 	}
 
 	repo := make(map[string]File)
-	for _, f := range fs {
+	for _, f := range files {
 		m.indexUpdate(repo, f)
 	}
+
+	m.rmut.Lock()
 	m.remote[nodeID] = repo
+	m.rmut.Unlock()
 
 	m.recomputeGlobal()
-	m.recomputeNeed()
+	m.recomputeNeedForFiles(files)
 }
 
 // IndexUpdate is called for incremental updates to connected nodes' indexes.
 // Implements the protocol.Model interface.
 func (m *Model) IndexUpdate(nodeID string, fs []protocol.FileInfo) {
-	m.Lock()
-	defer m.Unlock()
-
-	if m.trace["net"] {
-		log.Printf("NET IDXUP(in): %s: %d files", nodeID, len(fs))
+	var files = make([]File, len(fs))
+	for i := range fs {
+		files[i] = fileFromFileInfo(fs[i])
 	}
 
+	m.imut.Lock()
+	defer m.imut.Unlock()
+
+	if m.trace["net"] {
+		log.Printf("NET IDXUP(in): %s: %d files", nodeID, len(files))
+	}
+
+	m.rmut.Lock()
 	repo, ok := m.remote[nodeID]
 	if !ok {
 		log.Printf("WARNING: Index update from node %s that does not have an index", nodeID)
+		m.rmut.Unlock()
 		return
 	}
 
-	for _, f := range fs {
+	for _, f := range files {
 		m.indexUpdate(repo, f)
 	}
+	m.rmut.Unlock()
 
 	m.recomputeGlobal()
-	m.recomputeNeed()
+	m.recomputeNeedForFiles(files)
 }
 
-func (m *Model) indexUpdate(repo map[string]File, f protocol.FileInfo) {
+func (m *Model) indexUpdate(repo map[string]File, f File) {
 	if m.trace["idx"] {
 		var flagComment string
 		if f.Flags&protocol.FlagDeleted != 0 {
@@ -280,14 +330,16 @@ func (m *Model) indexUpdate(repo map[string]File, f protocol.FileInfo) {
 		return
 	}
 
-	repo[f.Name] = fileFromFileInfo(f)
+	repo[f.Name] = f
 }
 
-// Close removes the peer from the model and closes the underlyign connection if possible.
+// Close removes the peer from the model and closes the underlying connection if possible.
 // Implements the protocol.Model interface.
 func (m *Model) Close(node string, err error) {
-	m.Lock()
-	defer m.Unlock()
+	m.fq.RemoveAvailable(node)
+
+	m.pmut.Lock()
+	m.rmut.Lock()
 
 	conn, ok := m.rawConn[node]
 	if ok {
@@ -298,18 +350,25 @@ func (m *Model) Close(node string, err error) {
 	delete(m.protoConn, node)
 	delete(m.rawConn, node)
 
+	m.rmut.Unlock()
+	m.pmut.Unlock()
+
 	m.recomputeGlobal()
-	m.recomputeNeed()
+	m.recomputeNeedForGlobal()
 }
 
 // Request returns the specified data segment by reading it from local disk.
 // Implements the protocol.Model interface.
-func (m *Model) Request(nodeID, name string, offset uint64, size uint32, hash []byte) ([]byte, error) {
+func (m *Model) Request(nodeID, name string, offset int64, size uint32, hash []byte) ([]byte, error) {
 	// Verify that the requested file exists in the local and global model.
-	m.RLock()
+	m.lmut.RLock()
 	lf, localOk := m.local[name]
+	m.lmut.RUnlock()
+
+	m.gmut.RLock()
 	_, globalOk := m.global[name]
-	m.RUnlock()
+	m.gmut.RUnlock()
+
 	if !localOk || !globalOk {
 		log.Printf("SECURITY (nonexistent file) REQ(in): %s: %q o=%d s=%d h=%x", nodeID, name, offset, size, hash)
 		return nil, ErrNoSuchFile
@@ -329,44 +388,56 @@ func (m *Model) Request(nodeID, name string, offset uint64, size uint32, hash []
 	defer fd.Close()
 
 	buf := buffers.Get(int(size))
-	_, err = fd.ReadAt(buf, int64(offset))
+	_, err = fd.ReadAt(buf, offset)
 	if err != nil {
 		return nil, err
 	}
 
+	if m.limitRequestRate != nil {
+		for s := 0; s < len(buf); s += 1024 {
+			<-m.limitRequestRate
+		}
+	}
+
 	return buf, nil
 }
 
 // ReplaceLocal replaces the local repository index with the given list of files.
-// Change suppression is applied to files changing too often.
 func (m *Model) ReplaceLocal(fs []File) {
-	m.Lock()
-	defer m.Unlock()
-
 	var updated bool
 	var newLocal = make(map[string]File)
 
+	m.lmut.RLock()
 	for _, f := range fs {
 		newLocal[f.Name] = f
 		if ef := m.local[f.Name]; !ef.Equals(f) {
 			updated = true
 		}
 	}
+	m.lmut.RUnlock()
 
 	if m.markDeletedLocals(newLocal) {
 		updated = true
 	}
 
+	m.lmut.RLock()
 	if len(newLocal) != len(m.local) {
 		updated = true
 	}
+	m.lmut.RUnlock()
 
 	if updated {
+		m.lmut.Lock()
 		m.local = newLocal
+		m.lmut.Unlock()
+
 		m.recomputeGlobal()
-		m.recomputeNeed()
+		m.recomputeNeedForGlobal()
+
+		m.umut.Lock()
 		m.updatedLocal = time.Now().Unix()
 		m.lastIdxBcastRequest = time.Now()
+		m.umut.Unlock()
 	}
 }
 
@@ -374,33 +445,25 @@ func (m *Model) ReplaceLocal(fs []File) {
 // in protocol data types. Does not track deletes, should only be used to seed
 // the local index from a cache file at startup.
 func (m *Model) SeedLocal(fs []protocol.FileInfo) {
-	m.Lock()
-	defer m.Unlock()
-
+	m.lmut.Lock()
 	m.local = make(map[string]File)
 	for _, f := range fs {
 		m.local[f.Name] = fileFromFileInfo(f)
 	}
+	m.lmut.Unlock()
 
 	m.recomputeGlobal()
-	m.recomputeNeed()
+	m.recomputeNeedForGlobal()
 }
 
 // ConnectedTo returns true if we are connected to the named node.
 func (m *Model) ConnectedTo(nodeID string) bool {
-	m.RLock()
-	defer m.RUnlock()
+	m.pmut.RLock()
 	_, ok := m.protoConn[nodeID]
+	m.pmut.RUnlock()
 	return ok
 }
 
-// ProtocolIndex returns the current local index in protocol data types.
-func (m *Model) ProtocolIndex() []protocol.FileInfo {
-	m.RLock()
-	defer m.RUnlock()
-	return m.protocolIndex()
-}
-
 // RepoID returns a unique ID representing the current repository location.
 func (m *Model) RepoID() string {
 	return fmt.Sprintf("%x", sha1.Sum([]byte(m.dir)))
@@ -411,46 +474,62 @@ func (m *Model) RepoID() string {
 // repository changes.
 func (m *Model) AddConnection(rawConn io.Closer, protoConn Connection) {
 	nodeID := protoConn.ID()
-	m.Lock()
+	m.pmut.Lock()
 	m.protoConn[nodeID] = protoConn
 	m.rawConn[nodeID] = rawConn
-	m.Unlock()
-
-	m.RLock()
-	idx := m.protocolIndex()
-	m.RUnlock()
+	m.pmut.Unlock()
 
 	go func() {
+		idx := m.ProtocolIndex()
 		protoConn.Index(idx)
 	}()
+
+	m.initmut.Lock()
+	rw := m.rwRunning
+	m.initmut.Unlock()
+	if !rw {
+		return
+	}
+
+	for i := 0; i < m.parallelRequests; i++ {
+		i := i
+		go func() {
+			if m.trace["pull"] {
+				log.Println("PULL: Starting", nodeID, i)
+			}
+			for {
+				m.pmut.RLock()
+				if _, ok := m.protoConn[nodeID]; !ok {
+					if m.trace["pull"] {
+						log.Println("PULL: Exiting", nodeID, i)
+					}
+					m.pmut.RUnlock()
+					return
+				}
+				m.pmut.RUnlock()
+
+				qb, ok := m.fq.Get(nodeID)
+				if ok {
+					if m.trace["pull"] {
+						log.Println("PULL: Request", nodeID, i, qb.name, qb.block.Offset)
+					}
+					data, _ := protoConn.Request(qb.name, qb.block.Offset, qb.block.Size, qb.block.Hash)
+					m.fq.Done(qb.name, qb.block.Offset, data)
+				} else {
+					time.Sleep(1 * time.Second)
+				}
+			}
+		}()
+	}
 }
 
-func (m *Model) shouldSuppressChange(name string) bool {
-	sup := shouldSuppressChange(m.fileLastChanged[name], m.fileWasSuppressed[name])
-	if sup {
-		m.fileWasSuppressed[name]++
-	} else {
-		m.fileWasSuppressed[name] = 0
-		m.fileLastChanged[name] = time.Now()
-	}
-	return sup
-}
-
-func shouldSuppressChange(lastChange time.Time, numChanges int) bool {
-	sinceLast := time.Since(lastChange)
-	if sinceLast > maxFileHoldTimeS*time.Second {
-		return false
-	}
-	if sinceLast < time.Duration((numChanges+2)*minFileHoldTimeS)*time.Second {
-		return true
-	}
-	return false
-}
-
-// protocolIndex returns the current local index in protocol data types.
+// ProtocolIndex returns the current local index in protocol data types.
 // Must be called with the read lock held.
-func (m *Model) protocolIndex() []protocol.FileInfo {
+func (m *Model) ProtocolIndex() []protocol.FileInfo {
 	var index []protocol.FileInfo
+
+	m.lmut.RLock()
+
 	for _, f := range m.local {
 		mf := fileInfoFromFile(f)
 		if m.trace["idx"] {
@@ -462,13 +541,16 @@ func (m *Model) protocolIndex() []protocol.FileInfo {
 		}
 		index = append(index, mf)
 	}
+
+	m.lmut.RUnlock()
 	return index
 }
 
-func (m *Model) requestGlobal(nodeID, name string, offset uint64, size uint32, hash []byte) ([]byte, error) {
-	m.RLock()
+func (m *Model) requestGlobal(nodeID, name string, offset int64, size uint32, hash []byte) ([]byte, error) {
+	m.pmut.RLock()
 	nc, ok := m.protoConn[nodeID]
-	m.RUnlock()
+	m.pmut.RUnlock()
+
 	if !ok {
 		return nil, fmt.Errorf("requestGlobal: no such node: %s", nodeID)
 	}
@@ -482,29 +564,35 @@ func (m *Model) requestGlobal(nodeID, name string, offset uint64, size uint32, h
 
 func (m *Model) broadcastIndexLoop() {
 	for {
-		m.RLock()
+		m.umut.RLock()
 		bcastRequested := m.lastIdxBcastRequest.After(m.lastIdxBcast)
 		holdtimeExceeded := time.Since(m.lastIdxBcastRequest) > idxBcastHoldtime
-		m.RUnlock()
+		m.umut.RUnlock()
 
 		maxDelayExceeded := time.Since(m.lastIdxBcast) > idxBcastMaxDelay
 		if bcastRequested && (holdtimeExceeded || maxDelayExceeded) {
-			m.Lock()
+			idx := m.ProtocolIndex()
+
 			var indexWg sync.WaitGroup
 			indexWg.Add(len(m.protoConn))
-			idx := m.protocolIndex()
+
+			m.umut.Lock()
 			m.lastIdxBcast = time.Now()
+			m.umut.Unlock()
+
+			m.pmut.RLock()
 			for _, node := range m.protoConn {
 				node := node
 				if m.trace["net"] {
-					log.Printf("NET IDX(out/loop): %s: %d files", node.ID, len(idx))
+					log.Printf("NET IDX(out/loop): %s: %d files", node.ID(), len(idx))
 				}
 				go func() {
 					node.Index(idx)
 					indexWg.Done()
 				}()
 			}
-			m.Unlock()
+			m.pmut.RUnlock()
+
 			indexWg.Wait()
 		}
 		time.Sleep(idxBcastHoldtime)
@@ -512,13 +600,16 @@ func (m *Model) broadcastIndexLoop() {
 }
 
 // markDeletedLocals sets the deleted flag on files that have gone missing locally.
-// Must be called with the write lock held.
 func (m *Model) markDeletedLocals(newLocal map[string]File) bool {
 	// For every file in the existing local table, check if they are also
 	// present in the new local table. If they are not, check that we already
 	// had the newest version available according to the global table and if so
 	// note the file as having been deleted.
 	var updated bool
+
+	m.gmut.RLock()
+	m.lmut.RLock()
+
 	for n, f := range m.local {
 		if _, ok := newLocal[n]; !ok {
 			if gf := m.global[n]; !gf.NewerThan(f) {
@@ -532,41 +623,91 @@ func (m *Model) markDeletedLocals(newLocal map[string]File) bool {
 			}
 		}
 	}
+
+	m.lmut.RUnlock()
+	m.gmut.RUnlock()
+
 	return updated
 }
 
 func (m *Model) updateLocal(f File) {
+	var updated bool
+
+	m.lmut.Lock()
 	if ef, ok := m.local[f.Name]; !ok || !ef.Equals(f) {
 		m.local[f.Name] = f
+		updated = true
+	}
+	m.lmut.Unlock()
+
+	if updated {
 		m.recomputeGlobal()
-		m.recomputeNeed()
+		// We don't recomputeNeed here for two reasons:
+		// - a need shouldn't have arisen due to having a newer local file
+		// - recomputeNeed might call into fq.Add but we might have been called by
+		//   fq which would be a deadlock on fq
+
+		m.umut.Lock()
 		m.updatedLocal = time.Now().Unix()
 		m.lastIdxBcastRequest = time.Now()
+		m.umut.Unlock()
 	}
 }
 
-// Must be called with the write lock held.
+/*
+XXX: Not done, needs elegant handling of availability
+
+func (m *Model) recomputeGlobalFor(files []File) bool {
+	m.gmut.Lock()
+	defer m.gmut.Unlock()
+
+	var updated bool
+	for _, f := range files {
+		if gf, ok := m.global[f.Name]; !ok || f.NewerThan(gf) {
+			m.global[f.Name] = f
+			updated = true
+			// Fix availability
+		}
+	}
+	return updated
+}
+*/
+
 func (m *Model) recomputeGlobal() {
 	var newGlobal = make(map[string]File)
 
+	m.lmut.RLock()
 	for n, f := range m.local {
 		newGlobal[n] = f
 	}
+	m.lmut.RUnlock()
 
+	var available = make(map[string][]string)
+
+	m.rmut.RLock()
 	var highestMod int64
-	for _, fs := range m.remote {
+	for nodeID, fs := range m.remote {
 		for n, nf := range fs {
 			if lf, ok := newGlobal[n]; !ok || nf.NewerThan(lf) {
 				newGlobal[n] = nf
+				available[n] = []string{nodeID}
 				if nf.Modified > highestMod {
 					highestMod = nf.Modified
 				}
+			} else if lf.Equals(nf) {
+				available[n] = append(available[n], nodeID)
 			}
 		}
 	}
+	m.rmut.RUnlock()
+
+	for f, ns := range available {
+		m.fq.SetAvailable(f, ns)
+	}
 
 	// Figure out if anything actually changed
 
+	m.gmut.RLock()
 	var updated bool
 	if highestMod > m.updateGlobal || len(newGlobal) != len(m.global) {
 		updated = true
@@ -578,43 +719,110 @@ func (m *Model) recomputeGlobal() {
 			}
 		}
 	}
+	m.gmut.RUnlock()
 
 	if updated {
-		m.updateGlobal = time.Now().Unix()
+		m.gmut.Lock()
+		m.umut.Lock()
 		m.global = newGlobal
+		m.updateGlobal = time.Now().Unix()
+		m.umut.Unlock()
+		m.gmut.Unlock()
 	}
 }
 
-// Must be called with the write lock held.
-func (m *Model) recomputeNeed() {
-	m.need = make(map[string]bool)
-	for n, gf := range m.global {
-		lf, ok := m.local[n]
-		if !ok || gf.NewerThan(lf) {
-			if gf.Flags&protocol.FlagInvalid != 0 {
-				// Never attempt to sync invalid files
-				continue
+type addOrder struct {
+	n      string
+	remote []Block
+	fm     *fileMonitor
+}
+
+func (m *Model) recomputeNeedForGlobal() {
+	var toDelete []File
+	var toAdd []addOrder
+
+	m.gmut.RLock()
+
+	for _, gf := range m.global {
+		toAdd, toDelete = m.recomputeNeedForFile(gf, toAdd, toDelete)
+	}
+
+	m.gmut.RUnlock()
+
+	for _, ao := range toAdd {
+		m.fq.Add(ao.n, ao.remote, ao.fm)
+	}
+	for _, gf := range toDelete {
+		m.dq <- gf
+	}
+}
+
+func (m *Model) recomputeNeedForFiles(files []File) {
+	var toDelete []File
+	var toAdd []addOrder
+
+	m.gmut.RLock()
+
+	for _, gf := range files {
+		toAdd, toDelete = m.recomputeNeedForFile(gf, toAdd, toDelete)
+	}
+
+	m.gmut.RUnlock()
+
+	for _, ao := range toAdd {
+		m.fq.Add(ao.n, ao.remote, ao.fm)
+	}
+	for _, gf := range toDelete {
+		m.dq <- gf
+	}
+}
+
+func (m *Model) recomputeNeedForFile(gf File, toAdd []addOrder, toDelete []File) ([]addOrder, []File) {
+	m.lmut.RLock()
+	lf, ok := m.local[gf.Name]
+	m.lmut.RUnlock()
+
+	if !ok || gf.NewerThan(lf) {
+		if gf.Flags&protocol.FlagInvalid != 0 {
+			// Never attempt to sync invalid files
+			return toAdd, toDelete
+		}
+		if gf.Flags&protocol.FlagDeleted != 0 && !m.delete {
+			// Don't want to delete files, so forget this need
+			return toAdd, toDelete
+		}
+		if gf.Flags&protocol.FlagDeleted != 0 && !ok {
+			// Don't have the file, so don't need to delete it
+			return toAdd, toDelete
+		}
+		if m.trace["need"] {
+			log.Printf("NEED: lf:%v gf:%v", lf, gf)
+		}
+
+		if gf.Flags&protocol.FlagDeleted != 0 {
+			toDelete = append(toDelete, gf)
+		} else {
+			local, remote := BlockDiff(lf.Blocks, gf.Blocks)
+			fm := fileMonitor{
+				name:        gf.Name,
+				path:        path.Clean(path.Join(m.dir, gf.Name)),
+				global:      gf,
+				model:       m,
+				localBlocks: local,
 			}
-			if gf.Flags&protocol.FlagDeleted != 0 && !m.delete {
-				// Don't want to delete files, so forget this need
-				continue
-			}
-			if gf.Flags&protocol.FlagDeleted != 0 && !ok {
-				// Don't have the file, so don't need to delete it
-				continue
-			}
-			if m.trace["need"] {
-				log.Println("NEED:", ok, lf, gf)
-			}
-			m.need[n] = true
+			toAdd = append(toAdd, addOrder{gf.Name, remote, &fm})
 		}
 	}
+
+	return toAdd, toDelete
 }
 
-// Must be called with the read lock held.
-func (m *Model) whoHas(name string) []string {
+func (m *Model) WhoHas(name string) []string {
 	var remote []string
 
+	m.gmut.RLock()
+	m.rmut.RLock()
+
 	gf := m.global[name]
 	for node, files := range m.remote {
 		if file, ok := files[name]; ok && file.Equals(gf) {
@@ -622,24 +830,41 @@ func (m *Model) whoHas(name string) []string {
 		}
 	}
 
+	m.rmut.RUnlock()
+	m.gmut.RUnlock()
 	return remote
 }
 
+func (m *Model) deleteLoop() {
+	for file := range m.dq {
+		if m.trace["file"] {
+			log.Println("FILE: Delete", file.Name)
+		}
+		path := path.Clean(path.Join(m.dir, file.Name))
+		err := os.Remove(path)
+		if err != nil {
+			log.Printf("WARNING: %s: %v", file.Name, err)
+		}
+
+		m.updateLocal(file)
+	}
+}
+
 func fileFromFileInfo(f protocol.FileInfo) File {
 	var blocks = make([]Block, len(f.Blocks))
-	var offset uint64
+	var offset int64
 	for i, b := range f.Blocks {
 		blocks[i] = Block{
 			Offset: offset,
-			Length: b.Length,
+			Size:   b.Size,
 			Hash:   b.Hash,
 		}
-		offset += uint64(b.Length)
+		offset += int64(b.Size)
 	}
 	return File{
 		Name:     f.Name,
 		Flags:    f.Flags,
-		Modified: int64(f.Modified),
+		Modified: f.Modified,
 		Version:  f.Version,
 		Blocks:   blocks,
 	}
@@ -649,14 +874,14 @@ func fileInfoFromFile(f File) protocol.FileInfo {
 	var blocks = make([]protocol.BlockInfo, len(f.Blocks))
 	for i, b := range f.Blocks {
 		blocks[i] = protocol.BlockInfo{
-			Length: b.Length,
-			Hash:   b.Hash,
+			Size: b.Size,
+			Hash: b.Hash,
 		}
 	}
 	return protocol.FileInfo{
 		Name:     f.Name,
 		Flags:    f.Flags,
-		Modified: int64(f.Modified),
+		Modified: f.Modified,
 		Version:  f.Version,
 		Blocks:   blocks,
 	}

model/model_puller.go

@@ -1,258 +0,0 @@
-package model
-
-/*
-
-Locking
-=======
-
-These methods are never called from the outside so don't follow the locking
-policy in model.go.
-
-TODO(jb): Refactor this into smaller and cleaner pieces.
-TODO(jb): Increase performance by taking apparent peer bandwidth into account.
-
-*/
-
-import (
-	"bytes"
-	"errors"
-	"fmt"
-	"io"
-	"log"
-	"os"
-	"path"
-	"sync"
-	"time"
-
-	"github.com/calmh/syncthing/buffers"
-	"github.com/calmh/syncthing/protocol"
-)
-
-func (m *Model) pullFile(name string) error {
-	m.RLock()
-	var localFile = m.local[name]
-	var globalFile = m.global[name]
-	var nodeIDs = m.whoHas(name)
-	m.RUnlock()
-
-	if len(nodeIDs) == 0 {
-		return fmt.Errorf("%s: no connected nodes with file available", name)
-	}
-
-	filename := path.Join(m.dir, name)
-	sdir := path.Dir(filename)
-
-	_, err := os.Stat(sdir)
-	if err != nil && os.IsNotExist(err) {
-		os.MkdirAll(sdir, 0777)
-	}
-
-	tmpFilename := tempName(filename, globalFile.Modified)
-	tmpFile, err := os.Create(tmpFilename)
-	if err != nil {
-		return err
-	}
-
-	contentChan := make(chan content, 32)
-	var applyDone sync.WaitGroup
-	applyDone.Add(1)
-	go func() {
-		applyContent(contentChan, tmpFile)
-		tmpFile.Close()
-		applyDone.Done()
-	}()
-
-	local, remote := BlockDiff(localFile.Blocks, globalFile.Blocks)
-	var fetchDone sync.WaitGroup
-
-	// One local copy routine
-
-	fetchDone.Add(1)
-	go func() {
-		for _, block := range local {
-			data, err := m.Request("<local>", name, block.Offset, block.Length, block.Hash)
-			if err != nil {
-				break
-			}
-			contentChan <- content{
-				offset: int64(block.Offset),
-				data:   data,
-			}
-		}
-		fetchDone.Done()
-	}()
-
-	// N remote copy routines
-
-	var remoteBlocks = blockIterator{blocks: remote}
-	for i := 0; i < m.paralllelReqs; i++ {
-		curNode := nodeIDs[i%len(nodeIDs)]
-		fetchDone.Add(1)
-
-		go func(nodeID string) {
-			for {
-				block, ok := remoteBlocks.Next()
-				if !ok {
-					break
-				}
-				data, err := m.requestGlobal(nodeID, name, block.Offset, block.Length, block.Hash)
-				if err != nil {
-					break
-				}
-				contentChan <- content{
-					offset: int64(block.Offset),
-					data:   data,
-				}
-			}
-			fetchDone.Done()
-		}(curNode)
-	}
-
-	fetchDone.Wait()
-	close(contentChan)
-	applyDone.Wait()
-
-	err = hashCheck(tmpFilename, globalFile.Blocks)
-	if err != nil {
-		return fmt.Errorf("%s: %s (deleting)", path.Base(name), err.Error())
-	}
-
-	err = os.Chtimes(tmpFilename, time.Unix(globalFile.Modified, 0), time.Unix(globalFile.Modified, 0))
-	if err != nil {
-		return err
-	}
-
-	err = os.Chmod(tmpFilename, os.FileMode(globalFile.Flags&0777))
-	if err != nil {
-		return err
-	}
-
-	err = os.Rename(tmpFilename, filename)
-	if err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (m *Model) puller() {
-	for {
-		time.Sleep(time.Second)
-
-		var ns []string
-		m.RLock()
-		for n := range m.need {
-			ns = append(ns, n)
-		}
-		m.RUnlock()
-
-		if len(ns) == 0 {
-			continue
-		}
-
-		var limiter = make(chan bool, m.parallellFiles)
-		var allDone sync.WaitGroup
-
-		for _, n := range ns {
-			limiter <- true
-			allDone.Add(1)
-
-			go func(n string) {
-				defer func() {
-					allDone.Done()
-					<-limiter
-				}()
-
-				m.RLock()
-				f, ok := m.global[n]
-				m.RUnlock()
-
-				if !ok {
-					return
-				}
-
-				var err error
-				if f.Flags&protocol.FlagDeleted == 0 {
-					if m.trace["file"] {
-						log.Printf("FILE: Pull %q", n)
-					}
-					err = m.pullFile(n)
-				} else {
-					if m.trace["file"] {
-						log.Printf("FILE: Remove %q", n)
-					}
-					// Cheerfully ignore errors here
-					_ = os.Remove(path.Join(m.dir, n))
-				}
-				if err == nil {
-					m.Lock()
-					m.updateLocal(f)
-					m.Unlock()
-				}
-			}(n)
-		}
-
-		allDone.Wait()
-	}
-}
-
-type content struct {
-	offset int64
-	data   []byte
-}
-
-func applyContent(cc <-chan content, dst io.WriterAt) error {
-	var err error
-
-	for c := range cc {
-		_, err = dst.WriteAt(c.data, c.offset)
-		buffers.Put(c.data)
-		if err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
-func hashCheck(name string, correct []Block) error {
-	rf, err := os.Open(name)
-	if err != nil {
-		return err
-	}
-	defer rf.Close()
-
-	current, err := Blocks(rf, BlockSize)
-	if err != nil {
-		return err
-	}
-	if len(current) != len(correct) {
-		return errors.New("incorrect number of blocks")
-	}
-	for i := range current {
-		if bytes.Compare(current[i].Hash, correct[i].Hash) != 0 {
-			return fmt.Errorf("hash mismatch: %x != %x", current[i], correct[i])
-		}
-	}
-
-	return nil
-}
-
-type blockIterator struct {
-	sync.Mutex
-	blocks []Block
-}
-
-func (i *blockIterator) Next() (b Block, ok bool) {
-	i.Lock()
-	defer i.Unlock()
-
-	if len(i.blocks) == 0 {
-		return
-	}
-
-	b, i.blocks = i.blocks[0], i.blocks[1:]
-	ok = true
-
-	return
-}

model/model_test.go

@@ -12,13 +12,13 @@ import (
 )
 
 func TestNewModel(t *testing.T) {
-	m := NewModel("foo")
+	m := NewModel("foo", 1e6)
 
 	if m == nil {
 		t.Fatalf("NewModel returned nil")
 	}
 
-	if len(m.need) > 0 {
+	if fs, _ := m.NeedFiles(); len(fs) > 0 {
 		t.Errorf("New model should have no Need")
 	}
 
@@ -32,13 +32,19 @@ var testDataExpected = map[string]File{
 		Name:     "foo",
 		Flags:    0,
 		Modified: 0,
-		Blocks:   []Block{{Offset: 0x0, Length: 0x7, Hash: []uint8{0xae, 0xc0, 0x70, 0x64, 0x5f, 0xe5, 0x3e, 0xe3, 0xb3, 0x76, 0x30, 0x59, 0x37, 0x61, 0x34, 0xf0, 0x58, 0xcc, 0x33, 0x72, 0x47, 0xc9, 0x78, 0xad, 0xd1, 0x78, 0xb6, 0xcc, 0xdf, 0xb0, 0x1, 0x9f}}},
+		Blocks:   []Block{{Offset: 0x0, Size: 0x7, Hash: []uint8{0xae, 0xc0, 0x70, 0x64, 0x5f, 0xe5, 0x3e, 0xe3, 0xb3, 0x76, 0x30, 0x59, 0x37, 0x61, 0x34, 0xf0, 0x58, 0xcc, 0x33, 0x72, 0x47, 0xc9, 0x78, 0xad, 0xd1, 0x78, 0xb6, 0xcc, 0xdf, 0xb0, 0x1, 0x9f}}},
+	},
+	"empty": File{
+		Name:     "empty",
+		Flags:    0,
+		Modified: 0,
+		Blocks:   []Block{{Offset: 0x0, Size: 0x0, Hash: []uint8{0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14, 0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9, 0x24, 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c, 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55}}},
 	},
 	"bar": File{
 		Name:     "bar",
 		Flags:    0,
 		Modified: 0,
-		Blocks:   []Block{{Offset: 0x0, Length: 0xa, Hash: []uint8{0x2f, 0x72, 0xcc, 0x11, 0xa6, 0xfc, 0xd0, 0x27, 0x1e, 0xce, 0xf8, 0xc6, 0x10, 0x56, 0xee, 0x1e, 0xb1, 0x24, 0x3b, 0xe3, 0x80, 0x5b, 0xf9, 0xa9, 0xdf, 0x98, 0xf9, 0x2f, 0x76, 0x36, 0xb0, 0x5c}}},
+		Blocks:   []Block{{Offset: 0x0, Size: 0xa, Hash: []uint8{0x2f, 0x72, 0xcc, 0x11, 0xa6, 0xfc, 0xd0, 0x27, 0x1e, 0xce, 0xf8, 0xc6, 0x10, 0x56, 0xee, 0x1e, 0xb1, 0x24, 0x3b, 0xe3, 0x80, 0x5b, 0xf9, 0xa9, 0xdf, 0x98, 0xf9, 0x2f, 0x76, 0x36, 0xb0, 0x5c}}},
 	},
 }
 
@@ -53,11 +59,11 @@ func init() {
 }
 
 func TestUpdateLocal(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
-	if len(m.need) > 0 {
+	if fs, _ := m.NeedFiles(); len(fs) > 0 {
 		t.Fatalf("Model with only local data should have no need")
 	}
 
@@ -95,7 +101,7 @@ func TestUpdateLocal(t *testing.T) {
 }
 
 func TestRemoteUpdateExisting(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -106,13 +112,13 @@ func TestRemoteUpdateExisting(t *testing.T) {
 	}
 	m.Index("42", []protocol.FileInfo{newFile})
 
-	if l := len(m.need); l != 1 {
-		t.Errorf("Model missing Need for one file (%d != 1)", l)
+	if fs, _ := m.NeedFiles(); len(fs) != 1 {
+		t.Errorf("Model missing Need for one file (%d != 1)", len(fs))
 	}
 }
 
 func TestRemoteAddNew(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -123,13 +129,13 @@ func TestRemoteAddNew(t *testing.T) {
 	}
 	m.Index("42", []protocol.FileInfo{newFile})
 
-	if l1, l2 := len(m.need), 1; l1 != l2 {
-		t.Errorf("Model len(m.need) incorrect (%d != %d)", l1, l2)
+	if fs, _ := m.NeedFiles(); len(fs) != 1 {
+		t.Errorf("Model len(m.need) incorrect (%d != 1)", len(fs))
 	}
 }
 
 func TestRemoteUpdateOld(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -141,13 +147,13 @@ func TestRemoteUpdateOld(t *testing.T) {
 	}
 	m.Index("42", []protocol.FileInfo{newFile})
 
-	if l1, l2 := len(m.need), 0; l1 != l2 {
-		t.Errorf("Model len(need) incorrect (%d != %d)", l1, l2)
+	if fs, _ := m.NeedFiles(); len(fs) != 0 {
+		t.Errorf("Model len(need) incorrect (%d != 0)", len(fs))
 	}
 }
 
 func TestRemoteIndexUpdate(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -165,22 +171,22 @@ func TestRemoteIndexUpdate(t *testing.T) {
 
 	m.Index("42", []protocol.FileInfo{foo})
 
-	if _, ok := m.need["foo"]; !ok {
+	if fs, _ := m.NeedFiles(); fs[0].Name != "foo" {
 		t.Error("Model doesn't need 'foo'")
 	}
 
 	m.IndexUpdate("42", []protocol.FileInfo{bar})
 
-	if _, ok := m.need["foo"]; !ok {
+	if fs, _ := m.NeedFiles(); fs[0].Name != "foo" {
 		t.Error("Model doesn't need 'foo'")
 	}
-	if _, ok := m.need["bar"]; !ok {
+	if fs, _ := m.NeedFiles(); fs[1].Name != "bar" {
 		t.Error("Model doesn't need 'bar'")
 	}
 }
 
 func TestDelete(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -282,7 +288,7 @@ func TestDelete(t *testing.T) {
 }
 
 func TestForgetNode(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -292,8 +298,8 @@ func TestForgetNode(t *testing.T) {
 	if l1, l2 := len(m.global), len(fs); l1 != l2 {
 		t.Errorf("Model len(global) incorrect (%d != %d)", l1, l2)
 	}
-	if l1, l2 := len(m.need), 0; l1 != l2 {
-		t.Errorf("Model len(need) incorrect (%d != %d)", l1, l2)
+	if fs, _ := m.NeedFiles(); len(fs) != 0 {
+		t.Errorf("Model len(need) incorrect (%d != 0)", len(fs))
 	}
 
 	newFile := protocol.FileInfo{
@@ -303,14 +309,21 @@ func TestForgetNode(t *testing.T) {
 	}
 	m.Index("42", []protocol.FileInfo{newFile})
 
+	newFile = protocol.FileInfo{
+		Name:     "new file 2",
+		Modified: time.Now().Unix(),
+		Blocks:   []protocol.BlockInfo{{100, []byte("some hash bytes")}},
+	}
+	m.Index("43", []protocol.FileInfo{newFile})
+
 	if l1, l2 := len(m.local), len(fs); l1 != l2 {
 		t.Errorf("Model len(local) incorrect (%d != %d)", l1, l2)
 	}
-	if l1, l2 := len(m.global), len(fs)+1; l1 != l2 {
+	if l1, l2 := len(m.global), len(fs)+2; l1 != l2 {
 		t.Errorf("Model len(global) incorrect (%d != %d)", l1, l2)
 	}
-	if l1, l2 := len(m.need), 1; l1 != l2 {
-		t.Errorf("Model len(need) incorrect (%d != %d)", l1, l2)
+	if fs, _ := m.NeedFiles(); len(fs) != 2 {
+		t.Errorf("Model len(need) incorrect (%d != 2)", len(fs))
 	}
 
 	m.Close("42", nil)
@@ -318,16 +331,17 @@ func TestForgetNode(t *testing.T) {
 	if l1, l2 := len(m.local), len(fs); l1 != l2 {
 		t.Errorf("Model len(local) incorrect (%d != %d)", l1, l2)
 	}
-	if l1, l2 := len(m.global), len(fs); l1 != l2 {
+	if l1, l2 := len(m.global), len(fs)+1; l1 != l2 {
 		t.Errorf("Model len(global) incorrect (%d != %d)", l1, l2)
 	}
-	if l1, l2 := len(m.need), 0; l1 != l2 {
-		t.Errorf("Model len(need) incorrect (%d != %d)", l1, l2)
+
+	if fs, _ := m.NeedFiles(); len(fs) != 1 {
+		t.Errorf("Model len(need) incorrect (%d != 1)", len(fs))
 	}
 }
 
 func TestRequest(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -348,33 +362,8 @@ func TestRequest(t *testing.T) {
 	}
 }
 
-func TestSuppression(t *testing.T) {
-	var testdata = []struct {
-		lastChange time.Time
-		hold       int
-		result     bool
-	}{
-		{time.Unix(0, 0), 0, false},                    // First change
-		{time.Now().Add(-1 * time.Second), 0, true},    // Changed once one second ago, suppress
-		{time.Now().Add(-119 * time.Second), 0, true},  // Changed once 119 seconds ago, suppress
-		{time.Now().Add(-121 * time.Second), 0, false}, // Changed once 121 seconds ago, permit
-
-		{time.Now().Add(-179 * time.Second), 1, true},  // Suppressed once 179 seconds ago, suppress again
-		{time.Now().Add(-181 * time.Second), 1, false}, // Suppressed once 181 seconds ago, permit
-
-		{time.Now().Add(-599 * time.Second), 99, true},  // Suppressed lots of times, last allowed 599 seconds ago, suppress again
-		{time.Now().Add(-601 * time.Second), 99, false}, // Suppressed lots of times, last allowed 601 seconds ago, permit
-	}
-
-	for i, tc := range testdata {
-		if shouldSuppressChange(tc.lastChange, tc.hold) != tc.result {
-			t.Errorf("Incorrect result for test #%d: %v", i, tc)
-		}
-	}
-}
-
 func TestIgnoreWithUnknownFlags(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 
@@ -402,10 +391,7 @@ func TestIgnoreWithUnknownFlags(t *testing.T) {
 	}
 }
 
-func prepareModel(n int, m *Model) []protocol.FileInfo {
-	fs, _ := m.Walk(false)
-	m.ReplaceLocal(fs)
-
+func genFiles(n int) []protocol.FileInfo {
 	files := make([]protocol.FileInfo, n)
 	t := time.Now().Unix()
 	for i := 0; i < n; i++ {
@@ -416,33 +402,39 @@ func prepareModel(n int, m *Model) []protocol.FileInfo {
 		}
 	}
 
-	m.Index("42", files)
 	return files
 }
 
-func BenchmarkRecomputeGlobal10k(b *testing.B) {
-	m := NewModel("testdata")
-	prepareModel(10000, m)
+func BenchmarkIndex10000(b *testing.B) {
+	m := NewModel("testdata", 1e6)
+	fs, _ := m.Walk(false)
+	m.ReplaceLocal(fs)
+	files := genFiles(10000)
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		m.recomputeGlobal()
+		m.Index("42", files)
 	}
 }
 
-func BenchmarkRecomputeNeed10K(b *testing.B) {
-	m := NewModel("testdata")
-	prepareModel(10000, m)
+func BenchmarkIndex00100(b *testing.B) {
+	m := NewModel("testdata", 1e6)
+	fs, _ := m.Walk(false)
+	m.ReplaceLocal(fs)
+	files := genFiles(100)
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		m.recomputeNeed()
+		m.Index("42", files)
 	}
 }
 
-func BenchmarkIndexUpdate10000(b *testing.B) {
-	m := NewModel("testdata")
-	files := prepareModel(10000, m)
+func BenchmarkIndexUpdate10000f10000(b *testing.B) {
+	m := NewModel("testdata", 1e6)
+	fs, _ := m.Walk(false)
+	m.ReplaceLocal(fs)
+	files := genFiles(10000)
+	m.Index("42", files)
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
@@ -450,6 +442,34 @@ func BenchmarkIndexUpdate10000(b *testing.B) {
 	}
 }
 
+func BenchmarkIndexUpdate10000f00100(b *testing.B) {
+	m := NewModel("testdata", 1e6)
+	fs, _ := m.Walk(false)
+	m.ReplaceLocal(fs)
+	files := genFiles(10000)
+	m.Index("42", files)
+
+	ufiles := genFiles(100)
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.IndexUpdate("42", ufiles)
+	}
+}
+
+func BenchmarkIndexUpdate10000f00001(b *testing.B) {
+	m := NewModel("testdata", 1e6)
+	fs, _ := m.Walk(false)
+	m.ReplaceLocal(fs)
+	files := genFiles(10000)
+	m.Index("42", files)
+
+	ufiles := genFiles(1)
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		m.IndexUpdate("42", ufiles)
+	}
+}
+
 type FakeConnection struct {
 	id          string
 	requestData []byte
@@ -463,9 +483,13 @@ func (f FakeConnection) ID() string {
 	return string(f.id)
 }
 
+func (f FakeConnection) Option(string) string {
+	return ""
+}
+
 func (FakeConnection) Index([]protocol.FileInfo) {}
 
-func (f FakeConnection) Request(name string, offset uint64, size uint32, hash []byte) ([]byte, error) {
+func (f FakeConnection) Request(name string, offset int64, size uint32, hash []byte) ([]byte, error) {
 	return f.requestData, nil
 }
 
@@ -478,7 +502,7 @@ func (FakeConnection) Statistics() protocol.Statistics {
 }
 
 func BenchmarkRequest(b *testing.B) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	fs, _ := m.Walk(false)
 	m.ReplaceLocal(fs)
 

model/suppressor.go

@@ -0,0 +1,72 @@
+package model
+
+import (
+	"sync"
+	"time"
+)
+
+const (
+	MAX_CHANGE_HISTORY = 4
+)
+
+type change struct {
+	size int64
+	when time.Time
+}
+
+type changeHistory struct {
+	changes []change
+	next    int64
+	prevSup bool
+}
+
+type suppressor struct {
+	sync.Mutex
+	changes   map[string]changeHistory
+	threshold int64 // bytes/s
+}
+
+func (h changeHistory) bandwidth(t time.Time) int64 {
+	if len(h.changes) == 0 {
+		return 0
+	}
+
+	var t0 = h.changes[0].when
+	if t == t0 {
+		return 0
+	}
+
+	var bw float64
+	for _, c := range h.changes {
+		bw += float64(c.size)
+	}
+	return int64(bw / t.Sub(t0).Seconds())
+}
+
+func (h *changeHistory) append(size int64, t time.Time) {
+	c := change{size, t}
+	if len(h.changes) == MAX_CHANGE_HISTORY {
+		h.changes = h.changes[1:MAX_CHANGE_HISTORY]
+	}
+	h.changes = append(h.changes, c)
+}
+
+func (s *suppressor) suppress(name string, size int64, t time.Time) (bool, bool) {
+	s.Lock()
+
+	if s.changes == nil {
+		s.changes = make(map[string]changeHistory)
+	}
+	h := s.changes[name]
+	sup := h.bandwidth(t) > s.threshold
+	prevSup := h.prevSup
+	h.prevSup = sup
+	if !sup {
+		h.append(size, t)
+	}
+	s.changes[name] = h
+
+	s.Unlock()
+
+	return sup, prevSup
+}

model/suppressor_test.go

@@ -0,0 +1,113 @@
+package model
+
+import (
+	"testing"
+	"time"
+)
+
+func TestSuppressor(t *testing.T) {
+	s := suppressor{threshold: 10000}
+	t0 := time.Now()
+
+	t1 := t0
+	sup, prev := s.suppress("foo", 10000, t1)
+	if sup {
+		t.Fatal("Never suppress first change")
+	}
+	if prev {
+		t.Fatal("Incorrect prev status")
+	}
+
+	// bw is 10000 / 10 = 1000
+	t1 = t0.Add(10 * time.Second)
+	if bw := s.changes["foo"].bandwidth(t1); bw != 1000 {
+		t.Error("Incorrect bw %d", bw)
+	}
+	sup, prev = s.suppress("foo", 10000, t1)
+	if sup {
+		t.Fatal("Should still be fine")
+	}
+	if prev {
+		t.Fatal("Incorrect prev status")
+	}
+
+	// bw is (10000 + 10000) / 11 = 1818
+	t1 = t0.Add(11 * time.Second)
+	if bw := s.changes["foo"].bandwidth(t1); bw != 1818 {
+		t.Error("Incorrect bw %d", bw)
+	}
+	sup, prev = s.suppress("foo", 100500, t1)
+	if sup {
+		t.Fatal("Should still be fine")
+	}
+	if prev {
+		t.Fatal("Incorrect prev status")
+	}
+
+	// bw is (10000 + 10000 + 100500) / 12 = 10041
+	t1 = t0.Add(12 * time.Second)
+	if bw := s.changes["foo"].bandwidth(t1); bw != 10041 {
+		t.Error("Incorrect bw %d", bw)
+	}
+	sup, prev = s.suppress("foo", 10000000, t1) // value will be ignored
+	if !sup {
+		t.Fatal("Should be over threshold")
+	}
+	if prev {
+		t.Fatal("Incorrect prev status")
+	}
+
+	// bw is (10000 + 10000 + 100500) / 15 = 8033
+	t1 = t0.Add(15 * time.Second)
+	if bw := s.changes["foo"].bandwidth(t1); bw != 8033 {
+		t.Error("Incorrect bw %d", bw)
+	}
+	sup, prev = s.suppress("foo", 10000000, t1)
+	if sup {
+		t.Fatal("Should be Ok")
+	}
+	if !prev {
+		t.Fatal("Incorrect prev status")
+	}
+}
+
+func TestHistory(t *testing.T) {
+	h := changeHistory{}
+
+	t0 := time.Now()
+	h.append(40, t0)
+
+	if l := len(h.changes); l != 1 {
+		t.Errorf("Incorrect history length %d", l)
+	}
+	if s := h.changes[0].size; s != 40 {
+		t.Errorf("Incorrect first record size %d", s)
+	}
+
+	for i := 1; i < MAX_CHANGE_HISTORY; i++ {
+		h.append(int64(40+i), t0.Add(time.Duration(i)*time.Second))
+	}
+
+	if l := len(h.changes); l != MAX_CHANGE_HISTORY {
+		t.Errorf("Incorrect history length %d", l)
+	}
+	if s := h.changes[0].size; s != 40 {
+		t.Errorf("Incorrect first record size %d", s)
+	}
+	if s := h.changes[MAX_CHANGE_HISTORY-1].size; s != 40+MAX_CHANGE_HISTORY-1 {
+		t.Errorf("Incorrect last record size %d", s)
+	}
+
+	h.append(999, t0.Add(time.Duration(999)*time.Second))
+
+	if l := len(h.changes); l != MAX_CHANGE_HISTORY {
+		t.Errorf("Incorrect history length %d", l)
+	}
+	if s := h.changes[0].size; s != 41 {
+		t.Errorf("Incorrect first record size %d", s)
+	}
+	if s := h.changes[MAX_CHANGE_HISTORY-1].size; s != 999 {
+		t.Errorf("Incorrect last record size %d", s)
+	}
+
+}

model/walk.go

@@ -26,11 +26,16 @@ type File struct {
 
 func (f File) Size() (bytes int) {
 	for _, b := range f.Blocks {
-		bytes += int(b.Length)
+		bytes += int(b.Size)
 	}
 	return
 }
 
+func (f File) String() string {
+	return fmt.Sprintf("File{Name:%q, Flags:0x%x, Modified:%d, Version:%d, NumBlocks:%d}",
+		f.Name, f.Flags, f.Modified, f.Version, len(f.Blocks))
+}
+
 func (f File) Equals(o File) bool {
 	return f.Modified == o.Modified && f.Version == o.Version
 }
@@ -80,6 +85,9 @@ func (m *Model) loadIgnoreFiles(ign map[string][]string) filepath.WalkFunc {
 func (m *Model) walkAndHashFiles(res *[]File, ign map[string][]string) filepath.WalkFunc {
 	return func(p string, info os.FileInfo, err error) error {
 		if err != nil {
+			if m.trace["file"] {
+				log.Printf("FILE: %q: %v", p, err)
+			}
 			return nil
 		}
 
@@ -105,38 +113,36 @@ func (m *Model) walkAndHashFiles(res *[]File, ign map[string][]string) filepath.
 		}
 
 		if info.Mode()&os.ModeType == 0 {
-			fi, err := os.Stat(p)
-			if err != nil {
-				return nil
-			}
-			modified := fi.ModTime().Unix()
+			modified := info.ModTime().Unix()
 
-			m.RLock()
-			hf, ok := m.local[rn]
-			m.RUnlock()
+			m.lmut.RLock()
+			lf, ok := m.local[rn]
+			m.lmut.RUnlock()
 
-			if ok && hf.Modified == modified {
-				if nf := uint32(info.Mode()); nf != hf.Flags {
-					hf.Flags = nf
-					hf.Version++
+			if ok && lf.Modified == modified {
+				if nf := uint32(info.Mode()); nf != lf.Flags {
+					lf.Flags = nf
+					lf.Version++
 				}
-				*res = append(*res, hf)
+				*res = append(*res, lf)
 			} else {
-				m.Lock()
-				if m.shouldSuppressChange(rn) {
+				if cur, prev := m.sup.suppress(rn, info.Size(), time.Now()); cur {
 					if m.trace["file"] {
-						log.Println("FILE: SUPPRESS:", rn, m.fileWasSuppressed[rn], time.Since(m.fileLastChanged[rn]))
+						log.Printf("FILE: SUPPRESS: %q change bw over threshold", rn)
+					}
+					if !prev {
+						log.Printf("INFO: Changes to %q are being temporarily suppressed because it changes too frequently.", rn)
 					}
 
 					if ok {
-						hf.Flags = protocol.FlagInvalid
-						hf.Version++
-						*res = append(*res, hf)
+						lf.Flags = protocol.FlagInvalid
+						lf.Version++
+						*res = append(*res, lf)
 					}
-					m.Unlock()
 					return nil
+				} else if prev && !cur {
+					log.Printf("INFO: Changes to %q are no longer suppressed.", rn)
 				}
-				m.Unlock()
 
 				if m.trace["file"] {
 					log.Printf("FILE: Hash %q", p)
@@ -193,9 +199,9 @@ func (m *Model) Walk(followSymlinks bool) (files []File, ignore map[string][]str
 			return
 		}
 
-		for _, fi := range fis {
-			if fi.Mode()&os.ModeSymlink != 0 {
-				dir := path.Join(m.dir, fi.Name()) + "/"
+		for _, info := range fis {
+			if info.Mode()&os.ModeSymlink != 0 {
+				dir := path.Join(m.dir, info.Name()) + "/"
 				filepath.Walk(dir, m.loadIgnoreFiles(ignore))
 				filepath.Walk(dir, hashFiles)
 			}
@@ -222,15 +228,6 @@ func (m *Model) cleanTempFiles() {
 	filepath.Walk(m.dir, m.cleanTempFile)
 }
 
-func ignoreFilter(patterns map[string][]string, files []File) (filtered []File) {
-	for _, f := range files {
-		if !ignoreFile(patterns, f.Name) {
-			filtered = append(filtered, f)
-		}
-	}
-	return filtered
-}
-
 func ignoreFile(patterns map[string][]string, file string) bool {
 	first, last := path.Split(file)
 	for prefix, pats := range patterns {

model/walk_test.go

@@ -13,6 +13,7 @@ var testdata = []struct {
 	hash string
 }{
 	{"bar", 10, "2f72cc11a6fcd0271ecef8c61056ee1eb1243be3805bf9a9df98f92f7636b05c"},
+	{"empty", 0, "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"},
 	{"foo", 7, "aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f"},
 }
 
@@ -21,7 +22,7 @@ var correctIgnores = map[string][]string{
 }
 
 func TestWalk(t *testing.T) {
-	m := NewModel("testdata")
+	m := NewModel("testdata", 1e6)
 	files, ignores := m.Walk(false)
 
 	if l1, l2 := len(files), len(testdata); l1 != l2 {
@@ -55,32 +56,28 @@ func TestIgnore(t *testing.T) {
 		"foo":     {"bar", "z*"},
 		"foo/baz": {"quux", ".*"},
 	}
-	var files = []File{
-		{Name: "foo/bar"},
-		{Name: "foo/quux"},
-		{Name: "foo/zuux"},
-		{Name: "foo/qzuux"},
-		{Name: "foo/baz/t1"},
-		{Name: "foo/baz/t2"},
-		{Name: "foo/baz/bar"},
-		{Name: "foo/baz/quuxa"},
-		{Name: "foo/baz/aquux"},
-		{Name: "foo/baz/.quux"},
-		{Name: "foo/baz/zquux"},
-		{Name: "foo/baz/quux"},
-		{Name: "foo/bazz/quux"},
-	}
-	var remaining = []File{
-		{Name: "foo/quux"},
-		{Name: "foo/qzuux"},
-		{Name: "foo/baz/t1"},
-		{Name: "foo/baz/quuxa"},
-		{Name: "foo/baz/aquux"},
-		{Name: "foo/bazz/quux"},
+	var tests = []struct {
+		f string
+		r bool
+	}{
+		{"foo/bar", true},
+		{"foo/quux", false},
+		{"foo/zuux", true},
+		{"foo/qzuux", false},
+		{"foo/baz/t1", false},
+		{"foo/baz/t2", true},
+		{"foo/baz/bar", true},
+		{"foo/baz/quuxa", false},
+		{"foo/baz/aquux", false},
+		{"foo/baz/.quux", true},
+		{"foo/baz/zquux", true},
+		{"foo/baz/quux", true},
+		{"foo/bazz/quux", false},
 	}
 
-	var filtered = ignoreFilter(patterns, files)
-	if !reflect.DeepEqual(filtered, remaining) {
-		t.Errorf("Filtering mismatch\n  %v\n  %v", remaining, filtered)
+	for i, tc := range tests {
+		if r := ignoreFile(patterns, tc.f); r != tc.r {
+			t.Errorf("Incorrect ignoreFile() #%d; E: %v, A: %v", i, tc.r, r)
+		}
 	}
 }

protocol/PROTOCOL.md

@@ -193,6 +193,33 @@ model, the Index Update merely amends it with new or updated file
 information. Any files not mentioned in an Index Update are left
 unchanged.
 
+### Options (Type = 7)
+
+This informational message provides information about the client
+configuration, version, etc. It is sent at connection initiation and,
+optionally, when any of the sent parameters have changed. The message is
+in the form of a list of (key, value) pairs, both of string type.
+
+    struct OptionsMessage {
+        KeyValue Options<>;
+    }
+
+    struct KeyValue {
+        string Key;
+        string Value;
+    }
+
+Key ID:s apart from the well known ones are implementation
+specific. An implementation is expected to ignore unknown keys. An
+implementation may impose limits on key and value size.
+
+Well known keys:
+
+  - "clientId" -- The name of the implementation. Example: "syncthing".
+  - "clientVersion" -- The version of the client. Example: "v1.0.33-47". The
+    Following the SemVer 2.0 specification for version strings is
+    encouraged but not enforced.
+
 Example Exchange
 ----------------
 

protocol/common_test.go

@@ -5,7 +5,7 @@ import "io"
 type TestModel struct {
 	data   []byte
 	name   string
-	offset uint64
+	offset int64
 	size   uint32
 	hash   []byte
 	closed bool
@@ -17,7 +17,7 @@ func (t *TestModel) Index(nodeID string, files []FileInfo) {
 func (t *TestModel) IndexUpdate(nodeID string, files []FileInfo) {
 }
 
-func (t *TestModel) Request(nodeID, name string, offset uint64, size uint32, hash []byte) ([]byte, error) {
+func (t *TestModel) Request(nodeID, name string, offset int64, size uint32, hash []byte) ([]byte, error) {
 	t.name = name
 	t.offset = offset
 	t.size = size

protocol/messages.go

@@ -4,7 +4,7 @@ import "io"
 
 type request struct {
 	name   string
-	offset uint64
+	offset int64
 	size   uint32
 	hash   []byte
 }
@@ -42,7 +42,7 @@ func (w *marshalWriter) writeIndex(idx []FileInfo) {
 		w.writeUint32(f.Version)
 		w.writeUint32(uint32(len(f.Blocks)))
 		for _, b := range f.Blocks {
-			w.writeUint32(b.Length)
+			w.writeUint32(b.Size)
 			w.writeBytes(b.Hash)
 		}
 	}
@@ -56,7 +56,7 @@ func WriteIndex(w io.Writer, idx []FileInfo) (int, error) {
 
 func (w *marshalWriter) writeRequest(r request) {
 	w.writeString(r.name)
-	w.writeUint64(r.offset)
+	w.writeUint64(uint64(r.offset))
 	w.writeUint32(r.size)
 	w.writeBytes(r.hash)
 }
@@ -65,6 +65,14 @@ func (w *marshalWriter) writeResponse(data []byte) {
 	w.writeBytes(data)
 }
 
+func (w *marshalWriter) writeOptions(opts map[string]string) {
+	w.writeUint32(uint32(len(opts)))
+	for k, v := range opts {
+		w.writeString(k)
+		w.writeString(v)
+	}
+}
+
 func (r *marshalReader) readHeader() header {
 	return decodeHeader(r.readUint32())
 }
@@ -82,7 +90,7 @@ func (r *marshalReader) readIndex() []FileInfo {
 			nblocks := r.readUint32()
 			blocks := make([]BlockInfo, nblocks)
 			for j := range blocks {
-				blocks[j].Length = r.readUint32()
+				blocks[j].Size = r.readUint32()
 				blocks[j].Hash = r.readBytes()
 			}
 			files[i].Blocks = blocks
@@ -100,7 +108,7 @@ func ReadIndex(r io.Reader) ([]FileInfo, error) {
 func (r *marshalReader) readRequest() request {
 	var req request
 	req.name = r.readString()
-	req.offset = r.readUint64()
+	req.offset = int64(r.readUint64())
 	req.size = r.readUint32()
 	req.hash = r.readBytes()
 	return req
@@ -109,3 +117,14 @@ func (r *marshalReader) readRequest() request {
 func (r *marshalReader) readResponse() []byte {
 	return r.readBytes()
 }
+
+func (r *marshalReader) readOptions() map[string]string {
+	n := r.readUint32()
+	opts := make(map[string]string, n)
+	for i := 0; i < int(n); i++ {
+		k := r.readString()
+		v := r.readString()
+		opts[k] = v
+	}
+	return opts
+}

protocol/messages_test.go

@@ -46,7 +46,7 @@ func TestIndex(t *testing.T) {
 }
 
 func TestRequest(t *testing.T) {
-	f := func(name string, offset uint64, size uint32, hash []byte) bool {
+	f := func(name string, offset int64, size uint32, hash []byte) bool {
 		var buf = new(bytes.Buffer)
 		var req = request{name, offset, size, hash}
 		var wr = marshalWriter{w: buf}
@@ -117,3 +117,23 @@ func BenchmarkWriteRequest(b *testing.B) {
 		wr.writeRequest(req)
 	}
 }
+
+func TestOptions(t *testing.T) {
+	opts := map[string]string{
+		"foo":     "bar",
+		"someKey": "otherValue",
+		"hello":   "",
+		"":        "42",
+	}
+
+	var buf = new(bytes.Buffer)
+	var wr = marshalWriter{w: buf}
+	wr.writeOptions(opts)
+
+	var rd = marshalReader{r: buf}
+	var ropts = rd.readOptions()
+
+	if !reflect.DeepEqual(opts, ropts) {
+		t.Error("Incorrect options marshal/demarshal")
+	}
+}

protocol/protocol.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"sync"
 	"time"
 
@@ -18,6 +19,7 @@ const (
 	messageTypePing        = 4
 	messageTypePong        = 5
 	messageTypeIndexUpdate = 6
+	messageTypeOptions     = 7
 )
 
 const (
@@ -34,8 +36,8 @@ type FileInfo struct {
 }
 
 type BlockInfo struct {
-	Length uint32
-	Hash   []byte
+	Size uint32
+	Hash []byte
 }
 
 type Model interface {
@@ -44,7 +46,7 @@ type Model interface {
 	// An index update was received from the peer node
 	IndexUpdate(nodeID string, files []FileInfo)
 	// A request was made by the peer node
-	Request(nodeID, name string, offset uint64, size uint32, hash []byte) ([]byte, error)
+	Request(nodeID, name string, offset int64, size uint32, hash []byte) ([]byte, error)
 	// The peer node closed the connection
 	Close(nodeID string, err error)
 }
@@ -52,16 +54,18 @@ type Model interface {
 type Connection struct {
 	sync.RWMutex
 
-	id        string
-	receiver  Model
-	reader    io.Reader
-	mreader   *marshalReader
-	writer    io.Writer
-	mwriter   *marshalWriter
-	closed    bool
-	awaiting  map[int]chan asyncResult
-	nextId    int
-	indexSent map[string][2]int64
+	id          string
+	receiver    Model
+	reader      io.Reader
+	mreader     *marshalReader
+	writer      io.Writer
+	mwriter     *marshalWriter
+	closed      bool
+	awaiting    map[int]chan asyncResult
+	nextId      int
+	indexSent   map[string][2]int64
+	options     map[string]string
+	optionsLock sync.Mutex
 
 	hasSentIndex  bool
 	hasRecvdIndex bool
@@ -81,7 +85,7 @@ const (
 	pingIdleTime = 5 * time.Minute
 )
 
-func NewConnection(nodeID string, reader io.Reader, writer io.Writer, receiver Model) *Connection {
+func NewConnection(nodeID string, reader io.Reader, writer io.Writer, receiver Model, options map[string]string) *Connection {
 	flrd := flate.NewReader(reader)
 	flwr, err := flate.NewWriter(writer, flate.BestSpeed)
 	if err != nil {
@@ -101,6 +105,20 @@ func NewConnection(nodeID string, reader io.Reader, writer io.Writer, receiver M
 	go c.readerLoop()
 	go c.pingerLoop()
 
+	if options != nil {
+		go func() {
+			c.Lock()
+			c.mwriter.writeHeader(header{0, c.nextId, messageTypeOptions})
+			c.mwriter.writeOptions(options)
+			err := c.flush()
+			if err != nil {
+				log.Printf("Warning:", err)
+			}
+			c.nextId++
+			c.Unlock()
+		}()
+	}
+
 	return &c
 }
 
@@ -150,7 +168,7 @@ func (c *Connection) Index(idx []FileInfo) {
 }
 
 // Request returns the bytes for the specified block after fetching them from the connected peer.
-func (c *Connection) Request(name string, offset uint64, size uint32, hash []byte) ([]byte, error) {
+func (c *Connection) Request(name string, offset int64, size uint32, hash []byte) ([]byte, error) {
 	c.Lock()
 	if c.closed {
 		c.Unlock()
@@ -328,6 +346,11 @@ loop:
 				c.Unlock()
 			}
 
+		case messageTypeOptions:
+			c.optionsLock.Lock()
+			c.options = c.mreader.readOptions()
+			c.optionsLock.Unlock()
+
 		default:
 			c.close(fmt.Errorf("Protocol error: %s: unknown message type %#x", c.ID, hdr.msgType))
 			break loop
@@ -341,14 +364,15 @@ func (c *Connection) processRequest(msgID int, req request) {
 	c.Lock()
 	c.mwriter.writeUint32(encodeHeader(header{0, msgID, messageTypeResponse}))
 	c.mwriter.writeResponse(data)
-	err := c.flush()
+	err := c.mwriter.err
+	if err == nil {
+		err = c.flush()
+	}
 	c.Unlock()
 
 	buffers.Put(data)
 	if err != nil {
 		c.close(err)
-	} else if c.mwriter.err != nil {
-		c.close(c.mwriter.err)
 	}
 }
 
@@ -395,3 +419,9 @@ func (c *Connection) Statistics() Statistics {
 
 	return stats
 }
+
+func (c *Connection) Option(key string) string {
+	c.optionsLock.Lock()
+	defer c.optionsLock.Unlock()
+	return c.options[key]
+}

protocol/protocol_test.go

@@ -43,8 +43,8 @@ func TestPing(t *testing.T) {
 	ar, aw := io.Pipe()
 	br, bw := io.Pipe()
 
-	c0 := NewConnection("c0", ar, bw, nil)
-	c1 := NewConnection("c1", br, aw, nil)
+	c0 := NewConnection("c0", ar, bw, nil, nil)
+	c1 := NewConnection("c1", br, aw, nil, nil)
 
 	if ok := c0.ping(); !ok {
 		t.Error("c0 ping failed")
@@ -67,8 +67,8 @@ func TestPingErr(t *testing.T) {
 			eaw := &ErrPipe{PipeWriter: *aw, max: i, err: e}
 			ebw := &ErrPipe{PipeWriter: *bw, max: j, err: e}
 
-			c0 := NewConnection("c0", ar, ebw, m0)
-			NewConnection("c1", br, eaw, m1)
+			c0 := NewConnection("c0", ar, ebw, m0, nil)
+			NewConnection("c1", br, eaw, m1, nil)
 
 			res := c0.ping()
 			if (i < 4 || j < 4) && res {
@@ -94,8 +94,8 @@ func TestRequestResponseErr(t *testing.T) {
 			eaw := &ErrPipe{PipeWriter: *aw, max: i, err: e}
 			ebw := &ErrPipe{PipeWriter: *bw, max: j, err: e}
 
-			NewConnection("c0", ar, ebw, m0)
-			c1 := NewConnection("c1", br, eaw, m1)
+			NewConnection("c0", ar, ebw, m0, nil)
+			c1 := NewConnection("c1", br, eaw, m1, nil)
 
 			d, err := c1.Request("tn", 1234, 3456, []byte("hashbytes"))
 			if err == e || err == ErrClosed {
@@ -143,8 +143,8 @@ func TestVersionErr(t *testing.T) {
 	ar, aw := io.Pipe()
 	br, bw := io.Pipe()
 
-	c0 := NewConnection("c0", ar, bw, m0)
-	NewConnection("c1", br, aw, m1)
+	c0 := NewConnection("c0", ar, bw, m0, nil)
+	NewConnection("c1", br, aw, m1, nil)
 
 	c0.mwriter.writeHeader(header{
 		version: 2,
@@ -165,8 +165,8 @@ func TestTypeErr(t *testing.T) {
 	ar, aw := io.Pipe()
 	br, bw := io.Pipe()
 
-	c0 := NewConnection("c0", ar, bw, m0)
-	NewConnection("c1", br, aw, m1)
+	c0 := NewConnection("c0", ar, bw, m0, nil)
+	NewConnection("c1", br, aw, m1, nil)
 
 	c0.mwriter.writeHeader(header{
 		version: 0,
@@ -187,8 +187,8 @@ func TestClose(t *testing.T) {
 	ar, aw := io.Pipe()
 	br, bw := io.Pipe()
 
-	c0 := NewConnection("c0", ar, bw, m0)
-	NewConnection("c1", br, aw, m1)
+	c0 := NewConnection("c0", ar, bw, m0, nil)
+	NewConnection("c1", br, aw, m1, nil)
 
 	c0.close(nil)
 

usage.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"io"
+	"text/tabwriter"
+)
+
+func optionTable(w io.Writer, rows [][]string) {
+	tw := tabwriter.NewWriter(w, 2, 4, 2, ' ', 0)
+	for _, row := range rows {
+		for i, cell := range row {
+			if i > 0 {
+				tw.Write([]byte("\t"))
+			}
+			tw.Write([]byte(cell))
+		}
+		tw.Write([]byte("\n"))
+	}
+	tw.Flush()
+}
+
+func usageFor(fs *flag.FlagSet, usage string) func() {
+	return func() {
+		var b bytes.Buffer
+		b.WriteString("Usage:\n  " + usage + "\n")
+
+		var options [][]string
+		fs.VisitAll(func(f *flag.Flag) {
+			var dash = "-"
+			if len(f.Name) > 1 {
+				dash = "--"
+			}
+			var opt = "  " + dash + f.Name
+
+			if f.DefValue != "false" {
+				opt += "=" + f.DefValue
+			}
+
+			options = append(options, []string{opt, f.Usage})
+		})
+
+		if len(options) > 0 {
+			b.WriteString("\nOptions:\n")
+			optionTable(&b, options)
+		}
+
+		fmt.Println(b.String())
+	}
+}